Network training present
-
Upload
sopon-tumchota -
Category
Education
-
view
76 -
download
9
Transcript of Network training present
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Inter-Network
Training
Welcome to..
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Course Outline
Communication System Basic
Computer Networks Fundamental
Network Cabling System Concepts
Advance Computer Network Technology
Computer Network Protocol
DATA Transmission System
Computer Network Design Concepts
Computer Network Management System
Computer Network Security Concepts
Network Operating System (NOS)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 1
Communication
System Basic
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Communication System Concept.
Source
(Transmitter)
Destination
(Receiver)
Transmission Media
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Communication Mode
Simplex
Half Duplex (HDX)
Full Duplex (FDX)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Communication Protocols
Asynchronous Protocols
Not clock signal needed
Serial Communication
Low Speed Communication
Synchronous Protocols
Clock Signal Needed
Serial Communication
High Speed Communication
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Transmission Timing - Asynchronous
vs. Synchronous
Sampling timing – How to make the clocks in a transmitter and a receiver consistent?
Asynchronous transmission – sending shorter bit streams and timing is maintained for each small data block.
Synchronous transmission – To prevent timing draft between transmitter and receiver, their clocks are synchronized. For digital signal, this can be accomplished with Manchester encoding or differential Manchester encoding.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Interfaces
The point at which one device connects
to another
Standards define what signals are sent,
and how
Some standards also define physical
connector to be used
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Generic Communications
Interface Illustration
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
DTE and DCE
DTE DTE
host computer terminal
interface interface
modem modem
DCE
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
RS-232C (EIA 232C)
EIA’s “Recommended Standard” (RS)
Specifies mechanical, electrical,
functional, and procedural aspects of
the interface
Used for connections between DTEs and
voice-grade modems, and many other
applications
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*EIA-232-D
new version of RS-232-C adopted in
1987
improvements in grounding shield, test
and loop-back signals
the prevalence of RS-232-C in use made
it difficult for EIA-232-D to enter into the
marketplace
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*RS-449
EIA standard improving on capabilities of RS-
232-C
provides for 37-pin connection, cable lengths
up to 200 feet, and data rates up to 2 million
bps
covers functional/procedural portions of R-
232-C
electrical/mechanical specs covered by RS-422 &
RS-423
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*Functional Specifications
Specifies the role of the individual
circuits
Data circuits in both directions allow
full-duplex communication
Timing signals allow for synchronous
transmission (although asynchronous
transmission is more common)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*Procedural Specifications
Multiple procedures are specified
Simple example: exchange of asynchronous data on private line
Provides means of attachment between computer and modem
Specifies method of transmitting asynchronous data between devices
Specifies method of cooperation for exchange of data between devices
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*Mechanical Specifications
25-pin connector with a specific
arrangement of leads
DTE devices usually have male DB25
connectors while DCE devices have
female
In practice, fewer than 25 wires are
generally used in applications
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
DB-25 Female
DB-25 Male
*RS-232 DB-25 Connectors
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*RS-232 DB-25 Pin-outs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*RS-232 DB-9 Connectors
Limited RS-232
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*RS-422 DIN-8
Found on Macs
DIN-8 Male DIN-8 Female
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*Electrical Specifications
Specifies signaling between DTE and DCE
Uses NRZ-L encoding
Voltage < -3V = binary 1
Voltage > +3V = binary 0
Rated for <20Kbps and <15M
greater distances and rates are theoretically
possible, but not necessarily wise
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
*RS-232 Signals (Async)
Odd Parity
Even Parity
No Parity
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
What ?
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 2
Computer Network
Fundamentals
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
Basic Network Understanding
Introduction to Computer Network
Standards Organization
OSI of ISO Reference Model
Basic Networks Equipment
Networking Topology
Data-Communication Types
LAN (Local Area Networks)
MAN (Metropolitan Area Networks)
WAN (Wide Area Networks)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding
Introduction to Computer Network A group of computers linked
together
Access from one computer to another
Communicated via the network
Sharing resources-Disk, Data, Printer etc.
Site extended
Provide of physical routes along which information can flow
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
STANDARDS ORGANIZATION
CCITT =Consultative Committee for
International Telegraphy and Telephony
ISO = International Standards Organization
IEEE = Institute of Electrical and
Electronics Engineers
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
CCITT
Consultative committee for international
telegraphy and telephony
World standards organization for
telecommunication (Telephony)
Makes technical recommendations on
telegraph, telephone and data
communication interfaces
Some popular CCITT standards are :
V.24,V.35,X.25 etc.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
ISO
International Standards Organization or
International Organization for
Standardization
Defines and develops standards on a vast
variety of topics
Almost 100 countries are represented in
ISO U.S. representative is ANSI ( American
National Standards Institute )
Well know ISO standards OSI
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
IEEE
Institute of Electrical and Electronics
Engineers
Largest professional organization in the
world
Sponsors standardization group that
develops computing and electrical
standards
Well know IEEE standards : IEEE802 Series
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
THE ISO’s OSI REFERENCE MODEL
The Open System Interconnection
Developed in 1977 by ISO
Data Communication standards
Multi-vendor inter-operability
Universal accessibility
Serves as function guideline for communication tasks any communication standard
Concept behind model
Dividing difficult problems into subtasks
7 Layers model
Each layer executes specific functions
Each layer communicates with its peer in other computers
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
THE ISO’s OSI REFERENCE MODEL …
Application
Presentation
Session
Transport
Network
Data Link
Physical
7
6
5
4
3
2
1
• Reduce Complexity
• Standard Interfaces
• Modular Engineering
• Interoperable Technology
• Accelerate Evolution
• Teaching and Learning
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding … THE ISO’s OSI REFERENCE MODEL …
Physical media for OSI
Peer Protocol
Seven Layer Reference Model and Peer Protocols
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
Physical
HOST A HOST B
Segments
Packets
Frames
Bits
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
THE ISO’s OSI REFERENCE MODEL …
Application
Presentation
Session
Transport
Network
Data Link
Physical
HOST A
Application
Presentation
Session
Transport
Network
Data Link
Physical
HOST B
Segments
PK
FR
Bit
PK
FR
Bit
Relay Open System
Physical media for OSI Physical media for OSI
Communication Involving Relay Open System Communication Involving Relay Open System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding … THE ISO’s OSI REFERENCE MODEL …
Application
Presentation
Session
Transport
Network
Data Link
Physical Options from CCITT, IEEE etc.
802-2 (LLC)
9314-2
FDDI
802-3CSMA/CD
802-4Token-Bus
802-5Token-Ring
7776X.25
LAP/LAPB
7809
HDLC
8473
Connectionless Network Service
8208/CCITT X.25
Packet Level Protocol
8073/CCITT X.224
Connection-Oriented Transport Protocol
8327/CCITT X.225
Connection-Oriented Session Protocol
8823/CCITT X.226
Connection-Oriented Presentation Protocol
9040/9041
VT
8831/8832
JTM
8571/8572
FTAM
9595/9596
CMIP
OSI Layer Example ISO Protocol
ISO Protocol Examples
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding … PHYSICAL LAYER OSI MODEL
Defines Mechanical
Defines Electrical
Specification of Media
Defines Network Interface
Defines Media :
# Coaxial,
# Fiber Optic,
# Twisted Pair,
# etc. Transmission Medium
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Data-LINK LAYER OSI MODEL
MAC : Media Access Control
# Medium Access Management
# Framing
# Addressing
# Error Detection
# Example- CSMA/CD, Token Bus, Token Ring etc.
LLC : Logical Link Control
# Organizes group of information
# Detects and some time corrects errors
# Control data flow
# Example
- IBM’s used SDLC (Synchronous Data Link Control)
- ISO’s used HDLC (High-level Data Link Control)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding … Network LAYER OSI MODEL
Moving information across a network made up of multiple network segment
Destination calculates best path
According to path decided
Network Managed and Traffic Control
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Transport LAYER OSI MODEL
Network Flow Control
User Multiplex Address
Network Service
Sequence Number Check
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Session LAYER OSI MODEL
Communication Control
Map Network Address to User
Connected and Disconnect Control
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Presentation LAYER OSI MODEL
Translation Data
Information show to User
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Application LAYER OSI MODEL
Communication with User
Manage Communication between Computer
and Applications
Examples
# Mail transfer services,
# Terminal emulation, etc.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Basic Network Equipment
Repeaters
Bridges
Routers
Gateways
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Repeater
Connects between two segment of network
Retimes and regenerates the signal and sends
them
Used to extend the cable length
Used if number of nodes on a segment has
limits
Used if different physical media
Repeaters do not provide Traffic Isolation
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
PhysicalPhysical Physical
Repeater Function
Open System A Open System B
Comparing a Repeater to OSI
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Bridges
Unlike repeaters function
Extend the network
Provide segment network traffic (Filtering)
Forward packet from one segment to next segment (Forwarding)
Bridges are Categorized as# - Local Bridges
# - Remote Bridges
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
Physical
Bridge Function
Open System A Open System B
Comparing a Bridge to OSI
Physical Physical
Data Link Data Link
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Router
Routers do not know the exact Location of stations
Routers function using subnet address only
Routers use information in each packet or frame
Router determine destination address
Router repackage and retransmit data
Not responsible for end to end
Transmit packets up to next transmit point
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
Physical
Router Function
Open System A Open System B
Comparing a Router to OSI
Physical Physical
Data Link Data Link
Network Network
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Gate-Ways
Convert data moving between networks
Change format of message to application
program
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
Physical
Gateway Function
Open System A Open System B
Comparing a Gateway to OSI
Physical Physical
Data Link Data Link
Network Network
Transport Transport
Session Session
Presentation Presentation
ApplicationApplication
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Networking Topology
Bus Topology
Ring Topology
Star Topology
Mixed Topology (Bus-Star, etc.)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Bus Topology
Terminator - BUS - Terminator
A B C D
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Ring Topology
Token
Ring
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Star Topology
CC
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Network Understanding …
Mixed Topology
A B C D
CCCC
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Communication Type
Type of Computer Networks
Local Area Network ( LAN )
Metropolitan Area Network (MAN)
Wide Area Network (WAN
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Communication Type
Local Area Network (LAN)
Interlink age of Computer within a limited
location
High speed of Data exchange
( 10 - 100 Mbps or 1000 Mbps )
Low error rates
Inexpensive transmission media available
No Central control station
Connections to the outside world
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Communication Type
METROPOLITAN AREA NETWORK
(MAN)
Interlink age of many LANs within city
Uses LAN technology (Media, Access
method etc.)
Fairly large data transmission rate 10 - 100
Mbps or 1000 Mbps
Expensive transmission media (
Fiber Optic )
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Communication Type
Wide Area Networks (WAN)
Interlink age of many LANs and MANs
Low data transmission rate
# - below 1 or 2 Mbps
Example: Internet Network
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
LANs(Local Area Network)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Ethernet Local Area Network
Token Ring Local Area Network(4/16Mb/s)
FDDI (Fiber Distribution Data Interface)
100BaseT ( High Speed LAN)
ATM (Asynchronous Transfer Mode)
TYPE of LANs
( Local Area Network )
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
CSMA/CD Protocol Used
CSMA = Carrier Sent Multiple Access
CD = Collision Detected
Bus and Star Topology
1024 Node Per 1 Collision Domain (Segment)
28 Nodes Attach / Thin Net / 185 meters
100 Nodes Attach / Thick Net / 500meters
7 Bridges/Network
4 Repeaters/Network
ETHERNET
LOCAL AREA NETWORK
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
CSMA/CD PROTOCOL
Node A Node B Node C
Ethernet Media Access
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
CSMA/CD PROTOCOL (contd.)
Node A Node B Node C
Ethernet Media Access
TX RX RX
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
CSMA/CD PROTOCOL (contd.)
Node A Node B Node C
Ethernet Media Access
TXRX RX
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server
Direct Attach 28 Nodes for Thin Net. 185 meters
Direct Attach 100 Nodes for Thick Net. 500 meters
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server
Direct Attach 28 Nodes for Thin Net. 185 meters
Direct Attach 100 Nodes for Thick Net. 500 meters
Need More
Station OK !
Extend !
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server
Eth. Hub
8-16 W/S
Network Extended
Not Over 1024 W/S
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server
Eth. Hub
8-16 W/S
Network Extended
Not Over 1024 W/S
Need More
Station and Server
Extend !
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server1
Eth. Hub
8-32 W/S
Network Extended
Not Over 1024 W/S
Server2
Eth. Hub
8-32 W/S
Repeater
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server1
Eth. Hub
8-32 W/S
Server2
Eth. Hub
8-32 W/S
Repeater
HO !
Traffic Traffic
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ETHERNET LANs
Server1
Eth. Hub
8-32 W/S
Server2
Eth. Hub
8-32 W/S
Bridge
HO !
Good Good
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Token Passing Protocol
Ring and Star Topology
260 Nodes On Shielded Twisted Pair (100
meters)
230 Nodes On Unshielded Twisted Pair (300
meters)
Data Rate 4/16 Mb/s
7 Bridges/Network
4 Repeaters/Network
TOKEN RING
LOCAL AREA NETWORK
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE TOKEN RING LANs
Server1Server2
Server3
B
B
B
HU
B
HU
B
Ring 1Ring 2
Ring 3
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Based on ANSI X3T9.5 Fiber Distributed Data Interface Standard
100 Mbps Data Rate
Ring and Star Topology
Wide range of mainframe, workstation, and network interfaces
Dual Attached Stations (DAS)
Fault tolerance provided with dualcounter rotating ring
Dual Attached Concentrators (DAC)
Allow building of a tree configurations of SAS/SAC devices
Single Attached Stations/Concentrators (SAS/SAC)
Can be disconnected without affecting the DAC station
FDDI
LOCAL AREA NETWORK
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE FDDI LANs
XYPLEX 6601
ETHERNET SWITCH
FDDI Backbone 100 Mb/s
with DAS file servers, hubs, all switch
Clients attached to
wiring hubs for shared
10 Mbps connections
High performance clients
attached via dedicated
10 Mbps Ethernet
WW W
K
W
WW
W
K
K
Host
Server
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
It’s Ethernet- Only faster !
Based on existing standards and technology
Simple, low cost (Like Ethernet )
Uses existing cabling
Leverages network admin understanding of Ethernet minimal incremental training
Broad multi-vendor support
100Base-T/Fast Ethernet
LOCAL AREA NETWORK
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Speed 10 Mbps 100 Mbps
IEEE standard 802.3 802.3
Media Access Protocol CSMA/CD CSMA/CD
Topology Bus or Star Star
Cable support Coax,UTP,FO UTP,FO
Media interface Yes Yes
Full duplex Yes Yes
Broad industry support Yes Yes
Availability Now Now
100Base-T/Fast Ethernet (contd.)
LOCAL AREA NETWORK
Ethernet Fast Ethernet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE 100Base-T LANs
ETHERNET SWITCH
WW WK WW WKWW WK
Fast Ethernet SwitchHost A
100Mb
Host B
100Mb100 100
100
10/100
100
100Mb/s W-Group
10Mb/s W-Group
100Mb/s W-Group
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Provide fast packet switching than X.25
The packet very small fixed size
Multiple logical connections over one physical interface
Links equipped with ATM port via ATM card added to product
Capacity 45 Mbps to 2.488 Gbps
Application that current LAN/WANs can support
ATM
(Asynchronous Transfer Mode )
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAMPLE ATM NETWORK
Centrally Located Servers
Directly Attached to ATM
Switch/Network
Switched Ethernet
ATM
Backbone
155 Mb/s
Or Higher
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MANs
(Metropolitan Area Network)
WANs
(Wide Area Network)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Remote Access Terminal (WANs)
Used Lease or Line Dial up
LAN to LAN
Low speed in city called WANs
High speed in city called MANs
Low speed connect called WANs
MAN to MAN (WANs)
Low speed only
MANs and WANs CONNECTION
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
REMOTE ACCESS CONNECTION
Mod. or MUX
VAX Unix IBM
Mod. and MUX
Dial Line, ISDN or
Digital Lease Line
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
LANs to LANs
Low Speed CONNECTION
IBM
Remote
Bridge/Router
VAX
Remote
Bridge/Router
Dial up, Lease line, ISDN,
Satt., Micro wave etc.
WANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
LANs to LANs
High Speed CONNECTION
XYPLEX
VAX IBM
Unix
Remote
Bridge/Router
Remote
Bridge/Router
Remote
Bridge/Router
Remote
Bridge/Router
ATM
MANs
In City
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MANs to MANs
CONNECTION
San
Francisco
Chicago
New
York
Atlanta
Dallas
Los
Angeles
64 Kbps
64 Kbps
64 Kbps
64 Kbps
64 Kbps
64 Kbps
64 Kbps
64 Kbps
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 3
Network Cabling
System Concepts
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
Cabling System Structure
Type of Cables
Cabling System Reference
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Cabling System Structure
Horizontal Cabling System
Backbone Cabling System
Work Area
Type of Cable
Twisted Pairs
# Unshielded Twisted Pairs (UTP)
# Shielded Twisted Pairs (STP)
Fiber Optic Cable
# Multi-mode Fiber Optic
# Single-mode Fiber Optic
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Cabling System Concept
Cabling System Reference
# Cabling System Standard
# Modular Wiring
# Application Specific Pair Assignments
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept. Cabling System Structure
Horizontal Cabling System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Cabling System
Structure
Backbone Cabling
System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Cabling System StructureWork Area
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Type of Cable Unshielded Twisted Pairs (UTP)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Type of Cable
Shielded Twisted Pairs (STP)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
UTP Cable Category Category 3
# Transmission characteristics are specified up to 16 MHz.
Category 4
# Transmission characteristics are specified up to 20 MHz.
Category 5
# Transmission characteristics are specified up to 100 MHz.
Category 5e
# Transmission characteristics are specified up to 100 MHz.
Category 6
# Transmission characteristics will be specified up to 250 MHz.
Category 7
# Transmission characteristics will be specified up to 600 MHz.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Type of Cable
Fiber Optic Cable
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Fiber Optic Connector
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept. Sample Fiber Optic Cable
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
Cabling System Reference ANSI/TIA/EIA-568 Cabling Standard
# Establish a generic telecommunications cabling
# Support a multi-vendor environment
# Enable the planning and installation of a structured
# Cabling system for commercial buildings
# Establish performance and technical cabling system configurations
The standard specifies:
# Minimum requirements for telecommunications cabling
# Recommended topology and distances
# Media parameters which determine performance
# Connector and pin assignments to ensure interconnect ability
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Cabling System Concept.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 4
Advance ComputerNetwork Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
High Speed Technology Solution
LAN Switching Technology
VLAN Technology
Gigabit Ethernet
10 Gigabit Ethernet
Wireless LAN Technology
VPN (Virtual Private Networks)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
HIGH SPEED
Technology Solution
for
Local Area Network
(LANs)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Why High Bandwidth ?
Related Concept Overviews LAN Switching
dedicated bandwidth
Performance micro segmentation
Virtual LANs
Architecture
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The Need for Speed-Applications
CAD and CAE
Database processing
Deadline oriented, e.g. Publishing
Time critical, e.g. Trading floors
Multimedia
Centralized servers
Backup/Restore
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Desktop CPU Performance
1983 1986 1990 19930
10
20
30
40
50
60
70
80
90
100
1983 1986 1990 1993
YEAR
Year of Introduction
MIP
S
286 386486
PentiumIntel 80x86 MIPS
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The Problem for High Performance Systems
CPU Taxed by Hungry Applications
Bottlenecks occur in I/O data transfers
10 or 100 Mbps Network interface
cannot provide enough capacity for “ Big
Pipe” performance
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
BUS Performance
Micro channel Bus 32 Mbps
EISA Bus 33 Mbps
PCI Bus 132 Mbps
10 Mbps Ethernet
10 Mbps Ethernet
10 Mbps Ethernet
Are 10 Mbps Network Pipes Big Enough ?
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The Solution for High
Performance Systems
Maximizes Server-Client Performance
File, Printer, Storage, and Other
Network data throughput
High Capacity PCI bus Extends power of Pentium
processor onto the LAN
Eliminate wire, Bus bottlenecks and bottlenecks are in
the PC
Need an Adapter for Total System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Solution for Response Time
0 10 20 30 40 50 60
Local Hard
Drive
W10-SER10
W10-SER100
W100-
SER100
Seconds
SECONDS
Reference
Existing
Step 1
Step 2
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Infrastructure Follow Application
and Network Performance
83 85 87 89 91 93 95Intel 286
Intel 386
Intel 486
Pentium
Processor
10 Mbps
Switched 10 Mbps
100Base-T
Switched
100Base-T
Spreadsheets
Graphics Intensive
Documents
Replicated
Databases
Processor Speed Network Performance
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Shared Media Connectivity Typically lower cost per port
All shared media are subject to collisions
Ethernet star
Token Ring
FDDI
100Base
SERV. SERV.
Example of Ethernet Bus Topology Shared media
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
LAN Switching
Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understand Switching Basics
Describe packet-switch technologies
Such as Link Access Procedure Balanced (LAPB)
Frame Relay
Switched Multimegabit Data Service (SMDS)
X.25 Switching Networks
Refers to the technology a bridge many ways
Switches Connecting LAN segments
Use of MAC addresses to determine datagram needs to transmitted and reduce traffic.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Switched Connectivity
Other Switched
ATM
Switched Ethernet
High performance you need it
Dedicated bandwidth on other usersSERV.
SERV.
SERV.
SERV.
Example of Switch 10/100 Mbps
Fast Ethernet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understand Switching Basics
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understand Switching Basics
Switching in Ethernet Environment
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VLANs
(Virtual LANs)
Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
Virtual LAN (VLAN) is group hosts or network devices
That forms a single bridging domain
Layer 2 bridging protocols such as IEEE 802.10
VLANs network can take advantage ofBroadcast control
Security
Performance
Network management
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Virtual LANs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Construction Basics
Using an Ethernet port-switching hub.
ServerS1
ServerS2
0 1
2 3 4 5 6 7
C1C2 C4 C6
C3 C5
Switching
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Construction Basics
Implicit versus Explicit Tagging
The actual criteria used to define the logical
grouping of nodes into a VLAN can be
based upon implicit or explicit tagging.
Implicit tagging, which in effect eliminates
the use of a special tagging field inserted
into frames to packets,
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Construction Basics
Establishing vLANs based upon the use of switch ports..
ServerS1
ServerS2
0 1
2 3 4 5 6 7
C1C2 C4 C6
C3 C5
Switching
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Construction Basics
can be based upon MAC address, port
number of a switch used by a node,
protocol, or another parameter that node
can be logically grouped into.
Explicit tagging requires the addition of a
field into a frame or packet header.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VLAN Construction Basics
PORT-GROUPING VLANS
A port-grouping vLAN represents a virtual
LAN created by defining a group of ports on
a switch or router to form a broadcast
domain.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VLAN Construction Basics
Thus, another common name for this
type of vLAN is a port-based virtual LAN.
The hardware used to form a port-
grouping vLAN can range in scope from
an intelligent wiring hub to a switch or
sophisticated router;
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VLAN Construction Basics
Port-Group vLAN via an intelligent hub
VLAN 1 VLAN 3VLAN 2 VLAN 1
0 1 2 3 4 5 6 7
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MAC-BASED SWITCHING
MAC-based switching in recognition of
the use of media access control
addresses.
this method of vLAN creation is also
referred to as a “layer-2 vLAN”.
A vLAN-capable switch can provide a
high degree of versatility.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MAC-BASED SWITCHING
4 5
0 1 32
1 2 3 4 11 12 13 14
5 6 7 8 9 10
1615
server server
LAN Switch
vLAN 1 vLAN 2
Layer-2 vLANn
n
= Port n= MAC address
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MAC-BASED SWITCHING
Moving stations when using a layer-2 vLANnn
= Port n= MAC address
4 5
0 1 32
1 2 3 4 11 12 13 14
5 6 7 8 9 10
1615
server server
LAN Switch
vLAN 1 vLAN 2
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MAC-BASED SWITCHING
For example, selective users on a
segment connected to a port, as well as
individual workstations connected to
other ports on a switch, can be
configured into a broadcast to main
representing a virtual LAN.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
MAC-BASED SWITCHING
It should be noted that the “partitioning”
of a segment into two vLANs can result
in upper-layer problems.
This is because upper-layer protocols,
such as IP, require all stations on a
segment to have the same network
address.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
LAYER-3-BASES VLANS
A layer-3-based vLAN is constructed
using information contained in the
network layer header of packets.
There are a variety of methods that can
be used to create layer-3 vLANs.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Subnet-Based vLANs
Advantages
Flexibility of layer-3 vLANs, as a user moves to
another segment but retains his or her subnet
number, many switches will “follow” the
relocation, permitting moves to be accomplished
without requiring the reconfiguration of a LAN
switch.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Subnet-Based vLANs
vLAN creation based upon IP subnets
4 5
0 1 32
server server
LAN Switch
vLAN 1 vLAN 2
192.78.55.xxx
192.78.55.xxx
192.78.55.xxx
192.78.42.xxx
192.78.55.xxx
192.78.42.xxx
192.78.42.xxx
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Advantages
The configuration of vLANs can be
automatically formed, unlike port and MAC-
based virtual networks whose setup can be
tedious and time consuming.
A layer-3 vLAN is the fact that it supports
routing.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Disadvantages
Two limitations associated with vLAN using
Sub-netting.
configuration required to ensure network
stations are using the correct protocol and
network address.
the inability of some switches to support
multiple subnets on a port.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Protocol-Bases vLANs
The use of the layer-3 transmission protocol
as a method for vLAN creation provides a
mechanism which enables vLAN formation
to be based upon the layer-3 protocol.
Through the use of this method of vLAN
creation, it becomes relatively easy for
stations to belong to multiple vLANs.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Protocol-Bases vLANs
4 5
0 1 32
I/X X I/X I X X I I
I/X X I I/X X I
XI/X
server server
vLAN creation based upon protocol
n
I= Port n= IP Protocol= IPX Protocol= IPX & IP Protocols
X
I/X
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Protocol-Bases vLANs
Advantages
A major benefit associated with vLAN creation
based upon protocol is networking flexibility.
This flexibility enables stations to be moved
from one network segment to another without
losing vLAN membership.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Advantages
Another aspect associated with networking flexibility is
the ability to obtain the bandwidth advantages
associated with the use of LAN switches while tailoring
traffic to support different services.
To support this new requirement you could add a port
the LAN switch and connect a router to that port.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Advantages
Expanding a vLAN to support internet access
nI
= Port n= IP Protocol= IPX Protocol= IPX & IP Protocols
X
I/X
4 6
0 1 32
I/X X I/X I X X I I
I/X X I I/X X I
I/X
server
5
X
serverI
router Internet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Disadvantages
You must obtain equipment that supports
the use of protocols for vLAN creation as
well as verifies that stations are configured
correctly.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet
1000Base-XX Standard
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
Gigabit Ethernet
Is the IEEE by the 802.3z
Conform to the Ethernet Standard
# – Frame format
# – Minimum and maximum frame sizes
# – CSMA/CD access method
# – 802.2 LLC specifications
Provide forwarding between 10/100/1000 Mbps
10 times the performance of Fast Ethernet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
Uses of Gigabit Ethernet
Aggregating traffic between Ethernet clients and
centralized file or compute servers
Connecting multiple 100Base-T Fast Ethernet
switches through 100/1000 Mbps switches
Connecting both workstations and servers with
Gigabit Ethernet to run high-bandwidth
Applications, such as CAD/CAM, medical imaging,
and pre-press
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Gigabit Ethernet Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10 Gigabit Ethernet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
What is 10 Gigabit Ethernet?
Uses
IEEE 802.3 MAC
IEEE 802.3 Ethernet Frame Format
IEEE 802.3 Ethernet Frame Size
No Auto Negotiation
Full Duplex and Optics Only
Provides 10x Speed of 1 GigE
It’s simply 10 GigE or 802.3ae !
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10 GigE Standards – IEEE Groups
New Standards begins withthe Sponsor Group
Call for Interest and then,Study Group Formed
Project Authorization Requestto NesCom
Working Group Formed
Standards must be completedwithin 4 Years as of the PARapproval
Standards Review by RevCombefore the Sponsor Ballot
IEEE
IEEE-SA
Standards Board IEEE 802Sponsor Group
IEEE 802.3Working Group
IEEE 802.3aeTask Force
RevCom* NesCom**
Start Here!
End Here!
* Review Committee** New Standard Committee
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10 GigE Standards Time Table
Study Group Formed (HSSG*)
802.3aeFormed
802.3 Ballot
Sponsor Ballot
1999 2000 2001 2002
1st Draft Final Draft Standard
IEEE-SA Approval
* High Speed Study Group
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10 GigE Standard Interface
IEEE 802.ae LAN/MAN Fiber Type PMD Distance
10GBase-SR LANMMF 850nm Serial 25, 65, 300m
10GBase-SW WAN
10GBase-LR LANSMF
1310nm
Serial10km
10GBase-LW WAN
10GBase-ER LANSMF
1550nm
Serial40km
10GBase-EW WAN
10GBase-LX4 LANMMF 1310nm
WWDM
300m
SMF 10km
WAN: 9.953 Gbits/s; OC-192c Compatible
Serial: Wave length
WWDM: Wideband WDM (4 wave lengths: 4 x 3.125 Gbits/s)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10 GigE Interface Nomenclature
M: Media Type (or Wave Length) Short(850nm), Long(1310nm), Extra Long(1550nm)
C: Coding Scheme X(8B/10B), R(64B/66B), W(64B/66B with simplified
SONET/SDH)
W: Number of Wavelengths 1 (Implied), 4
10GBASE- M WC
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10GBASE-R/10GBASE-W/10GBASE-X
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multi Mode Fiber Consideration:
Modal Dispersion
The PMDs for MMF supports at most 300 meters Typically, 30 meter or 80 meter
The Distance limitation due to Modal Bandwidth Approx. Distance = Modal Bandwidth / Bandwidth
E.g., 10 GigE over 62.5um MMF with 200 MHzKm modal bandwidth
# 20 meter = 200 MhzKm / 10000 MHz
To overcome this issue, LX4 has been proposed But it has brought out more problems in terms of complexity
and cost; it’s WDM any!
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Architecture of 802.3ae
WAN PHY LAN PHY
* Figure from 802.3ae Draft
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
10 GigE Concept View
* Source: 10GEA White Paper
Optics(PMD) PHY MAC
Fiber
Fiber
Reco
ncilia
tion
PCS
PM
A
XG
MII
WIS
(Optio
n)
LAN PHY WAN PHY LAN PHY-WDM
Reconciliation: Converting messages of MAC layer into electrical signal
PCS: Physical Coding Sub layer, Coding(64B/66B, 8B/10B)
WIS: WAN Interface Sub layer, For WAN PHY
PMA: Physical Media Attachment, Serialize or desterilize signals
XGMII: 10G Media Independent Interface
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Essential 10 GigE Features
Redundancy, Reliability, Scalability 802.3ad aggregation
802.1w (Rapid Spanning Tree Protocol)
802.1s VLAN Grouping
Ring and Mesh Topology Support Optimal deployment of Ethernet networks in Metro Area
Rapid protection mechanism for fail-over on Ring and Mesh topology
Integrated Switching and Routing Simultaneous L2 and L3 support
QoS? 10 GigE = Over Provisioning = Simple to manage, Rocket
performance
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Solutions where 10 GigE Bright Light
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Metro Solution: The Keys
Minimum TCO (Total Cost of Ownership)
Implementation (Reuse of Backbone IP Networks if
Any)
Operation
Maintenance
Training
Services
Abundant bandwidth supply for a fraction of price
for the legacy service
A variety of services and accounting schemes
There is 10 GigE !
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Metro Service Network Leveraging Existing IP Backbones
Existing Regional IP Backbone - Seoul
Existing Regional IP Backbone - Daejun
Existing Regional IP Backbone - Bussan
Existing Regional IP Backbone - Gwangju
Metro Ring in 10GBASE-LR/ER
Legacy POS interface
10 GigE
1 GigE
POS
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Inside Internet Exchange: Enhanced Traffic
Load Balancing and Simplified Topology Massive 1 GigE
Trunk
Inefficient Traffic
Load Balancing
Wiring complexity
Increased Packet
Delay
A-IX
B-IX (Major Peer)
10 GigE
2 x 1 GigE
1 GigE
Trunk
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Internet Data Center
High Performance Server with Gigabit NIC
Gigabit-over-Copper NIC is expected to dominate
high-end servers
Up-link
1 GigE Trunks? No!
10 GigE brings out:
• Better Load Balancing• Faster Response Time• Easier to Manage• Easier to Implement• Ultimately, Lower TCO1 GigE
10 GigE
L4 Switch
Switch/Router
100 M
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
High Speed Campus Network
ISP A
ISP B
10 GigERing
100Base-FXUp to 40Km
POS OC-3c
1 GigE
100 M
Mission Critical High-End Servers
PCs
High-End Servers
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
WireLess
Local Area Network
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Uses
Key drivers are mobility and
accessibility
Easily change work locations in the
office
Internet access at airports, cafes,
conferences, etc.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Benefits
Increased productivity
Improved collaboration
No need to reconnect to the network
Ability to work in more areas
Reduced costs
No need to wire hard-to-reach areas
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Standards
IEEE 802.11
IEEE 802.11b
IEEE 802.11a
IEEE 802.11e
Hiper LAN/2
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
802.11
Published in June 1997
2.4GHz operating frequency
1 to 2 Mbps throughput
Can choose between frequency hopping
or direct sequence spread modulation
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
802.11b
Published in late 1999 as supplement to
802.11
Still operates in 2.4GHz band
Data rates can be as high as 11 Mbps
Only direct sequence modulation is
specified
Most widely deployed today
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
802.11a
Also published in late 1999 as a supplement
to 802.11
Operates in 5GHz band (less RF interference
than 2.4GHz range)
Users Orthogonal Frequency Division
Multiplexing (OFDM)
Supports data rates up to 54 Mbps
Currently no products available, expected in
fourth quarter
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
802.11e
Currently under development
Working to improve security issues
Extensions to MAC layer, longer keys,
and key management systems
Adds 128-bit AES encryption
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
HiperLAN/2
Development led by the European
Telecommunications Standards Institute
(ETSI)
Operates in the 5 GHz range, uses OFDM
technology, and support data rates over
50Mbps like 802.11a
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Functionality
Basic Configuration
WLAN Communication
WLAN Packet Structure
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Configuration
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
802.11 Communication
CSMA/CA (Carrier Sense Multiple
Access/Collision Avoidance) instead of
Collision Detection
WLAN adapter cannot send and receive
traffic at the same time on the same
channel
Four-Way Handshake
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Four-Way Handshake
Source Destination
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI Reference Model: Phy
Network Oper. System Network Layer
Guarantees delivery data
Drivers LLC Layer
send/receive data
LAN ControllerMAC Layer
data into/out frame
MODEM Physical Layer
frame into/out phy frame
Physical Layer
IEEE: MAC Layer
IEEE: LLC Layer
Network Layer
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Wireless LAN Technologies
InfraredSpread
SpectrumNarrow Band
Direct Sequence
FrequencyHopping
Wireless LAN technologies (overview)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Wireless LAN technologies (Infrared)
low power infrared light as the carrier
No license required
Very restricted mobility, limited coverage
high data rate (10 Mbps, 16 Mbps)
Line-of-Sight Infrared
no objects in the path between two stations
Diffuse Infrared
uses reflections to set-up wireless link
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Wireless LAN technologies (Narrow Band) Dedicated band (18 GHz)
License required
ISM band (915 MHz, 2.4 GHz, 5.8 GHz)
unlicensed (special modulation)
extremely low output power i.e. limited coverage
high data rate (up to 10 Mbps) on short distance
Europe - DECT band (1.8 GHz)
based on voice standard
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
• 915 MHz only in the Americas (region 2)
• 2.4 GHz for global availability (region 1,2,3)
1 2 3 4 6 8 10 20 30 40 60 100
GHz
1
2
3
ISM Frequency Allocations
Worldwide
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Wireless LAN technologies (Spread Spectrum)
Unlicensed usage (ISM band)
No line of sight requirement (indoor)
High link reliability
Built-in transmission security
Two techniques used:
Direct Sequence
Frequency Hopping
Standard Radio
Transmission
Spread Spectrum
Transmission
Frequency Spectrum (MHz)
2400 2500
PowerPower
FrequencyFrequency
88 103 2400
FM Band
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Module contents
Technologies overview
Spread Spectrum
Direct Sequence
Frequency Hopping
Modulation
DBPSK/DQPSK
CCK
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiple Access MethodsMultiple users share the available spectrum
FREQUENCY
TIME
User 3
User 2
User 1
• Multiple users share
the same frequency
channel sequentially
• Time slot sequence
repeats over and over
TDMA
TIME
FREQUENCY
CODE
CDMA
also known as “Spread Spectrum”
User 3
User 2
User 1
• Channel is “spread” over wide frequency
band
• Many users share the same frequency
band at the same time
• Each user is assigned a unique “code”
to identify and separate
them
FREQUENCY
TIME
FDMA
1 2 3
Each user assigned a
different frequency -
like ordinary radio
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Spread Spectrum Technologies DS vs. FH
Direct Sequence Each symbol is transmitted over
multiple frequencies at the same time
Very efficient (no overhead)
Higher speed than FH at comparable distances
System capacity (multiple channels) higher than FH
Frequency Hopping Sequential use of multiple frequencies
Hop sequence and rate will vary
“End hop waste time”
COMPLETE WAVEBAND ALLOCATED
Time
Time
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Spreading: Information signal (I.e. a “symbol”) is multiplied by a unique, high rate digital code which stretches (spreads) its bandwidth before transmission.
Code bits are called “Chips”.
Sequence is called “Barker Code”
Source and
Channel
Coding
RF
Modulator
Code
Generator
X
Multiplier
Code Bits (Chips)
Digital Signal (Bits)
Frequency
Spectrum
f
“Spread” Frequency
Spectrum
f
Spread Spectrum Technologies Direct Sequence transmitter
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
At the receiver, the spread signal is multiplied again by a synchronized replica of the same code, and is “de-spread” and recovered
The outcome of the process is the original “symbol”
RF
Demodulator
Channel
and
Source
Decoding
Code
Generator
X
Multiplied
Code Bits (Chips)
De-Spread
Signal
f
“Spread” Frequency
Spectrum
f
Digital Signal (Bits)
Spread Spectrum Technologies Direct Sequence receiver
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VIRTUAL PRIVATE NETWORKS
(VPN)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Traditional Connectivity
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
What is VPN?
Virtual Private Network is a type of private
network that uses public telecommunication,
such as the Internet, instead of leased lines to
communicate.
Became popular as more employees worked
in remote locations.
Terminologies to understand how VPNs work.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Private Networks vs. Virtual Private Networks
Employees can access the network (Intranet) from remote locations.
Secured networks.
The Internet is used as the backbone for VPNs
Saves cost tremendously from reduction of equipment and maintenance costs.
Scalability
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Remote Access Virtual Private Network
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Four Protocols used in VPN
PPTP -- Point-to-Point Tunneling Protocol
L2TP -- Layer 2 Tunneling Protocol
IPsec -- Internet Protocol Security
SOCKS – is not used as much as the ones above
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VPN Encapsulation of Packets
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Types of Implementations
What does “implementation” mean in
VPNs?
3 types
Intranet – Within an organization
Extranet – Outside an organization
Remote Access – Employee to Business
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Virtual Private Networks (VPN)Basic Architecture
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Device Types
What it means
3 types
Hardware
Firewall
Software
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Device Types: Hardware
Usually a VPN type of router
Pros
• Highest network throughput
• Plug and Play
• Dual-purpose
Cons
• Cost
• Lack of flexibility
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Device Types: Firewall
More security?
Pros
• “Harden” Operating System
• Tri-purpose
• Cost-effective
Cons
• Still relatively costly
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Device Types: Software
Ideal for 2 end points not in same org.
Great when different firewalls
implemented
Pros
• Flexible
• Low relative cost
Cons
• Lack of efficiency
• More labor training
required
• Lower productivity;
higher labor costs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Eliminating the need for expensive long-
distance leased lines
Reducing the long-distance telephone
charges for remote access.
Transferring the support burden to the
service providers
Operational costs
Advantages: Cost Savings
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Flexibility of growth
Efficiency with broadband technology
Advantages: Scalability
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VPNs require an in-depth understanding of public network security issues and proper deployment of precautions
Availability and performance depends on factors largely outside of their control
Immature standards
VPNs need to accommodate protocols other than IP and existing internal network technology
Disadvantages
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Applications: Site-to-Site VPNs
Large-scale encryption between multiple fixed sites such as remote offices and central offices
Network traffic is sent over the branch office Internet connection
This saves the company hardware and management expenses
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Site-to-Site VPNs
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Applications: Remote Access
Encrypted connections between mobile or
remote users and their corporate networks
Remote user can make a local call to an ISP, as
opposed to a long distance call to the corporate
remote access server.
Ideal for a telecommuter or mobile sales people.
VPN allows mobile workers & telecommuters to
take advantage of broadband connectivity.
i.e. DSL, Cable
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 5
ComputerNetworking Protocol
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
Sample Network Protocol
TCP/IP v4
TCP/IP v6
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
AppleTalk
DECnet Phase IV
DECnet Phase V
Novell IPX/SPX
TCP/IP
Net BIOS
XEROX XNS
SNA
X.25
Frame Relay
HDLC
SDLC
Sample Network Protocol
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
TCP/IP Protocol
(IPv4)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The Transmission Control Protocol / Internet Protocol
Best of all Inter-Networking protocol
Developed in 1970
More 300 hardware/software vendor product
Protocol follows four layer
Network Access Layer
Internet Layer
Host-Host Layer
Process/Application Layer
TCP/IP Protocol
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI: Open System Internetworking Model
Application
Presentation
Session
Transport
Network
Data Link
Physical
OSI
File, print, message, database, and application services
Data encryption, compression, and data translation services
Dialog control
End to end connection
Routing
Framing, CRC
Physical topology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
DoD: Department of Defense Model
TCP/IP was created by the department of
Defense
It was intended initially for military use
TCP/IP became a standard for the internet as
well as LANs
It consists of four layers
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
DoD Reference Model
Process/Applications
Host-to-Host
Internet
Network Access
DoD
Telnet, FTP, LDP, SMNP, TFTP, SMTP, NFS, X Windows
TCP, UDP
ICMP,BootP,ARP, RARP,IP
Ethernet, Fast Ethernet, Token Ring, FDDI
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI and TCP/IP
Process/Applications
Host-to-Host
Internet
Network Access
DoD
Application
Presentation
Session
Transport
Network
Data Link
Physical
OSI
TCP/IP is a condensed version of the OSI model
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Controls access to locally LAN or WAN
Network specific and multiple
implementation the internet
Network Access Layer
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Routing and Switching of data through
the communication network
Forwarding a data on the network
address of the destination
Fragmentation and Reassembly of the
data
Internet Layer
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Provide virtual circuit service between
end user application
Responsible for end to end connection
between host process
Error control and detecting missing
information
Flow control that fast sender with slower
receiver
Connection control
Host-Host Layer
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Provide TCP/IP Application:
FTP ; File Transfer Protocol
Telnet; Terminal Emulation Protocol
SMTP; Simple Mail Transfer Protocol
SNMP; Simple Network Management
Protocol
etc.
Process/Application Layer
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IP Addresses
Every host must be configured with a pre-assigned IP address
DHCP can be used to automate IP assignment
IP has: a network address and host or node address
IP addresses are 32-bits long
It’s divided into 4 section each a byte long and separated by a dot ( not flat )
IP could be noted: Dotted-decimal, Binary or Hexadecimal
IP uses Three levels of addressing: network, subnet and host
It's similar to phone numbers: Area code, prefix and final segment
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IP Addresses (continued)
IP differentiates networks with their size
IP ranks three main classes: Class A, Class B and Class C
IP mandates the leading bits section of the address for each different network class
There are additional classes, Class D and Class E
IP addresses are assigned by the InterNIC
Class A: (126 Networks, 16,777,214 nodes) link
Class B: (16,384networks,65,534 nodes)
Class C:(2,097,157 networks 254 nodes
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IP Addresses (continued)
Bit 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Class A 0 Network Host Host Host
Class B 1 0 Network Network Host Host
Class C 1 1 0 Network Network Network Host
Class D 1 1 1 0 Multicast Address Multicast Address Multicast Address Multicast Address
Class E 1 1 1 1 0 Reserved Reserved Reserved Reserved
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Invalid IP addresses
0,255 and 127 can’t be used in the first byte of the network address
0: means this network
255: broadcast
127: loop back
0,255 are invalid node Ids
0: this network
255 broadcast
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IP Host names
It’s an alias assigned to computer
Multiple names can be assigned to the same host
As the number of nodes grew on the internet, the flat database became harder to manage
DNS divides the name space into smaller partitions: Domains
Name management can be delegated to organizations on the internet
The top level domains are: arpa, int, edu,gov, mil, net, org, com
FQDN fully qualified domain names: ftp.apple.com
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Subnet Masking
Sub-netting is used to divide a network to smaller subnets
Physical layers protocols impose limitations on the number of nodes on network segments
Having all the nodes on the same network imposes use of the same technology (EX: Ethernet or Token Rings)
Networks that have Nodes across wide geographical area can also be a problem
TCP/IP supports breaking a network to smaller subnets
Bits are borrowed from node ID to subnet the network
The number of subnets is 2^n - 2 where n is the number of bits borrowed
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Routing
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Routing (continued)
There are two types of routers: static and dynamic
Dynamic routers build and update routing tables
automatically
Dynamic routers use RIP routing Information protocol
Static routers can only communicate with networks
directly connected to their interface
Entries have to be manually put in routing tables
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Sample TCPIP Network
Carrier
ServiceFASTLA
NE
S C I T E C
F5voice data packet bandwidth manager
Network
Control
Terminal
Ethernet LAN NET_A
N11
FASTL
ANE
S C I T E C
F5voice data packet bandwidth manager
Ethernet LAN NET_B
N23
FASTL
ANE
S C I T E C
F5voice data packet bandwidth manager
Ethernet LAN NET_C
N20
126.10.10.1
126.10.10.2
126.10.10.3
122.8.8.6
122.8.8.7
122.8.8.8
122.8.8.11122.8.8.10122.8.8.8
123.4.4.10
123.4.4.5123.4.4.4
123.4.4.3123.4.4.2123.4.4.1
121.10.10.3
121.10.10.6121.10.10.5121.10.10.4
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Examples of TCP/IP applications
FTP
Allows file transfer
Uses telnet to let client logon to server
Telnet
Terminal emulation
allows clients to appear as virtual terminals to remote hosts
SNMP
Used to collect and manipulate information about devices on the network
Also used to monitor networks
SNMP clients send trap messages to management stations
SMTP
Used to queue and deliver mail messages
NFS
Allows two different file systems on the network to share files
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
TCP/IP Protocol
IPv6Background
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Why a New IP?
only compelling reason: more addresses!
for billions of new devices,e.g., cell phones, PDAs, appliances, cars, etc.
for billions of new users,e.g., in China, India, etc.
for “always-on” access technologies,e.g., xDSL, cable, Ethernet-to-the-home, etc.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IPv4 Address Space Left?
~ half the IPv4 space is unallocated
if size of Internet is doubling each year,
does this mean only one year’s worth?!
no, because today we deny unique IPv4
addresses to most new hosts
we make them use methods like NAT, PPP, etc.
to share addresses
but new types of applications and new types
of access need unique addresses!
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Why Are NATs?
they won’t work for large numbers of
“servers”, i.e., devices that are “called”
by others (e.g., IP phones)
they inhibit deployment of new
applications and services
they compromise the performance,
robustness, security, and
manageability of the Internet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Summary of Main IPv6 Benefits
expanded addressing capabilities
server-less auto-configuration (“plug-n-play”)and reconfiguration
more efficient and robust mobility mechanisms
built-in, strong IP-layer encryption and authentication
streamlined header format and flow identification
improved support for options / extensions
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IPv6 Standard Protocol
The 4 billion addresses available in IPv4
Working on IPv6 since the early 1990s
Expanded addressing from 32-bit to 128-bit
Addresses are n:n:n:n:n:n:n:n n = 4 digit
Hexadecimal integer, 16 ¥ 8 = 128 address
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IPV6
Addressing & Routing
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Text Representation of Addresses
“preferred” form:1080:0:FF:0:8:800:200C:417A
compressed form: FF01:0:0:0:0:0:0:43
becomes FF01::43
IPv4-compatible: 0:0:0:0:0:0:13.1.68.3
or ::13.1.68.3
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Address Types
unicast (one-to-one)
- global
- link-local
- site-local
- IPv4-compatible
multicast (one-to-many)
anycast (one-to-nearest)
reserved
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IPv6 Standard Protocol
Unicast
Unicast is a communication between a single host
and a single receiver
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IPv6 Standard Protocol
Multicast
Multicast is communication between a
single host and multiple receivers
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IPv6 Standard Protocol
Anycast Anycast is a communication between a single sender and a
list of addresses
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 6
Data Transmission
System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
Data Transmission Equipment
Modem (Mod-De Modulation)
MUX (Multiplexer De-Multiplexer)
xDSL (Digital Sub-Scriber Line)
PSTN (Public Switching Telephone Networks)
ISDN (Integrate Service Digital Networks)
Frame Relay Networks
ATM (Asynchronous Transfer Mode)
SDH/SONET (Synchronous Optical Networks)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Transmission Equipment
Modem
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Transmission Equipment
Modem Type
Analog Modem
# Asynchronous
# Synchronous
Digital Modem
# Synchronous
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Access Via ISPs
Consumers and businesses typically gain Internet access via ISPs. Many ISPs provide a variety of connection interfaces including:
Dial-in modem connections
ISDN
Cable modems
T/E-n and fractional T/E-n
Wireless service providers (WSPs) provide wireless Internet access for users with wireless modems, smart phones, and Web-enabled PDAs, or handheld computers
Despite increasing use of DSL and cable modems, dial-in access over voice-grade analog circuits is the most common form of Internet access for consumers
Point-to-point (PPP) protocol is the most widely used protocol over dial-up connections
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Character Encoding
Encoding is one of the first requirements of a data communication network
Character encoding involves the conversion of human-readable characters to corresponding fixed-length series of bits
Bits can be represented as discrete signals and therefore can be easily transmitted or received over communication mediaWhen bits are represented as discrete signals, such as
different voltage levels, they are in a digital format
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Codes
Several character encoding schemes are widely used in data communication systems including: ASCII (American Standard Code for Information Interchange)
EBCDIC (Extended Binary-Coded Decimal Interchange Code)
Unicode (aka ISO 10646)
Touch-tone telephone code
As illustrated in, these vary in the number of bits used to represent each character as well as the total number of characters that can be represented
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Transmitting Encoded Data
The bits that represent encoded characters can be transmitted simultaneously (parallel transmission) or one at time (serial transmission) – see Figure 6-2
Serial transmission is more widely used than parallel transmission for data communication
Parallel transmission is used for communication between components within a computer
In serial transmission, encoded characters can either be transmitted one at a time (asynchronous transmission) or in blocks (synchronous transmission) – see Figure 6-5
Figure 6-4 illustrates asynchronous transmission of a single character.
UART provides the interface between parallel transmission within the computer and serial transmission ports. It also plays a key role in formatting encoded characters for asynchronous transmission
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-2
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-4
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-5
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Flow
Data communication networks, including modem-to-modem communications, must have some mechanism for control over the flow of data between senders and receivers
Three elementary kinds of data flow are: Simplex
Half-duplex
Full-duplex
These are illustrated in Figures 6-6 and 6-7
Most modems in use today support both full- and half-duplex communication
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-7
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Interfaces and Interface Standards
There are two major classes of data communication equipment:
Data communication equipment (DCE): this includes modems,
media, switches, routers, satellite transponders, etc.)
Data terminating equipment (DTE): this includes terminals, servers,
workstations, printers, etc.)
The physical interface is the manner in these two classes are
joined together (see Figure 6-8)
A wide range of interface standards exist including
RS-232-C
RS-422, RS-423, RS-449
A variety of ISO and ITU interfaces
USB and FireWire
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-8
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
RS-232-C
EIA’s RS-232-C standard is arguably the most important physical
layer standard
It is the most widely accepted standard for transferring encoded
characters across copper wires between a computer or terminal
and a modem
RS-232-C uses voltage levels between –15 and +15 volts (see
Figure 6-9); negative voltages are used to represent 1 bits and
positive voltages are use to represent 0 bits
This standard does not specify size or kind of connectors to be
used in the interface. It does define 25 signal leads (see Table 6-
4). 25-pin connectors and 9-pin connectors are most common,
but other kinds of connectors are sometimes used
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-9
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Data Transmission
All communication media are capable of transmitting data in either digital or analog form.
Voice-grade dial-up circuits are typically analog, however, relative to analog transmission, digital transmission has several advantages:Lower error rates
Higher transmission speeds
No digital-analog conversion
Security
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Analog Transmission
Data is represented in analog form when transmitted over analog voice-grade dial-up circuits (see Figure 6-14)
This is done by varying the amplitude, frequency, or phase of the carrier signal (carrier wave) raised during the handshaking process at the start of a communication session between two modems
During handshaking, the two modems raise a carrier signal and agree on how it will be manipulated to represent 0 and 1 bits
In some modulation schemes, more than one of the carrier signal’s characteristics are simultaneously manipulated
Modems (modulator/demodulators) are the devices used to translate the digital signals transmitted by computers into corresponding analog signals used to represent bits over analog dial-up circuits (see Figure 6-13)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-13
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-17
Figure 6-19
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-20
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Phase Modulation
Figure 6-24
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Bit Rates and Bandwidth
The bandwidth of an analog channel is the difference between the minimum and maximum frequencies it can carry A voice-grade dial-up circuit can transmit frequencies
between 300 and 3400 Hz and thus has a bandwidth of 3100 Hz
For digital circuits, bandwidth is a measure of the amount of data that can be transmitted per unit. Bits per second (bps) is the most widely used measure for digital circuits
Over time, bit rates (bps) have also become on of the key measures of modem performance (e.g. a 56 Kbps modem) However, modem bit rates are not necessarily an accurate
reflection of their data throughput rates
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Baud Rate
Baud rate is a measure of the number of discrete signals that can be transmitted (or received) per unit of time
A modem’s baud rate measures the number of signals that it is capable of transmitting (or receiving) per second Baud rate represents the number of times per second that a modem
can modulate (or demodulate) the carrier signal to represent bits
Although baud rate and bit rate are sometimes used interchangeably to refer to modem data transfer speeds, these are only identical when each signal transmitted (or received) represents a signal bit A modem’s bit rate is typically higher than its baud rate because
each signal transmitted or received may represent a combination of two or more bits
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Dibits, Tribits, Quadbits, and QAM
Dibits are a transmission mode in which each signal conveys two bits of data
With tribits, each carrier signal modulation represents a 3-bit combination
Quadbits is a transmission mode in which each signal represents a 4-bit combination. Sixteen distinct carrier signal modulations are required for quadbits
Phase modulation is common on today’s modems because it lends itself well to the implementation of dibits, tribits, and quadbits (see Figure 6-27)
Quadrature amplitude modulation (QAM) is widely used in today’s modems. Many versions of QAM represent far more than 4-bits per baud
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-27
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Modem Capabilities
Modems differ in several dimensions including:
The type of medium they can be connected to (copper-based, fiber-optic, wireless)
Speed
Connection options (such as support for call waiting)
Support for voice-over-data
Data compression algorithms
Security features (such as password controls or callback)
Error detection and recovery mechanisms
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Modem Speed
Over time, the evolution of modem standards has corresponded with increases in modem speeds (see Table 6-6)
In 2002, V.92 is the newest modem standard
V.92 is backward compatible with V.90 but is capable of upstream data rates of 48,000
Like V.90, V.92 modems leverage PCM for downstream links
A variety of factors contribute to modem speed and data throughput including:
Adaptive line probing
Dynamic speed shifts
Fallback capabilities
Fallforword capabilities
Data compression
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Table 6-6
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Compression
Modem data compression capabilities enable modems to have
data throughput rates greater than their maximum bit rates
This is accomplished by substituting large strings of repeating
characters or bits with shorter codes
The data compression process is illustrated in Figure 6-29
Widely supported standards for data compression include (see
Table 6-7):
V.42bis --- up to 4:1 compression using the Lempel Ziv algorithm
MNP Class 5 --- supports 1.3:1 and 2:1 ratios (via Huffman encoding
and run-length encoding)
MNP Class 7 – up to 3:1 compression
V.44 --- capable of 20% to 100% improvements over V.42bis
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-29
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Table 6-7
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Error Detection and Recovery
In order to ensure that data is not changed or lost during transmission, error-detection and recovery processes are standard aspects of modem operations
The general process is as follows (see Figure 6-30) During handshaking, the modem pair determines the error
checking approach that will be used
The sender sends the error-check along with the data
The receiver calculates its own error-check on received data and compares it to that transmitted by the sender
If the receiver’s error-check matches the sender’s, no error is detected; a mismatch indicates a transmission error
Detected errors trigger error recovery mechanisms
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-30
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Error Sources
There are many sources of data communication transmission errors including:Signal attenuation
Impulse noise
Crosstalk
Echo
Phase jitter
Envelope delay distortion
White noise
Electromagnetic interference (EMI)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Error Impacts
Errors cause bits to be changed (corrupted) during transmission; without error-detection mechanisms, erroneous data could be received and used in application processing
Figure 6-32 illustrates a transmission error caused by noise
Table 6-8 indicates that longer impulse noises can corrupt multiple bits, especially as transmission speed increases
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-32
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Table 6-8
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Error Prevention
Error prevention approaches used in data communications include:Line conditioning
Adaptive protocols (such as adaptive line probing, fallback, adaptive size packet assembly)
Shielding
Repeaters and amplifiers
Better equipment
Flow control# RTS/CTS
# XON/OFF
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Error Detection Approaches
Error detection processes vary in complexity and robustness. They include: Parity checking (see Table 6-9)
Longitudinal redundancy checks (LRC) – see Table 6-10
Checksums
Cyclical redundancy checks (most widely used and robust)
# CRC-12
# CRC-16
# CRC-32
Sequence checks
Other approaches include check digits, hash totals, byte counts, and character echoing
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Table 6-9
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Table 6-10
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Error Recovery
Automatic repeat request (ARQ) is the most widely used error-recovery approach in data communications. In this approach, the receiver requests retransmission if an error occurs. There are three major kinds of ARQ: Discrete ARQ (aka stop-and-wait ARQ). Sender waits for an ACK or NAK
before transmitting another packet
Continuous ARQ (aka go-back-N ARQ). Sender keeps transmitting until a NAK is returned; sender retransmits that packet and all others after it
Selective ARQ. Sender only retransmits packets with errors
Forward error correction codes involve sending additional redundant information with the data to enable receivers to correct some of the errors they detect. Hamming code and Trellis Coded Modulation are examples
Error control/recovery standards include MNP Class 4, V.42, and LAP-M (see Table 6-12)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Modem/Computer Communications
One of the roles of communication software is to enable users to view
and modify modem settings (see Figure 6-33) such as:
error control (see Figure 6-33a and Figure 6-33c)
transmission speed (see Figure 6-33b)
flow control (see Figure 6-33c)
data compression (see Figure 6-33c)
UART settings (see Figure 6-33d)
Most communication software issues Hayes AT command set
instructions to modems
When a user wants to establish a communication session over a dial-up
connection, communication software sends a setup string to the
modem.
The setup string specifies what settings are to be used for
communicating with other modems and how the modem and
computer will interact.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Figure 6-33c
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Special Purpose Modems
A variety of special purpose modems are found in
data communication networks including:
multiport modems
short-haul modems
modem eliminators
fiber optic modems
cable modems
ISDN modems
CSU/DSU
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Transmission Equipment
Multiplexer De-Multiplexer (MUX)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
Telcom networks divided into 2 types:
Access network: attach to clients
Core network: connects access networks to each
other, provide services
Client/access interface: UNI (User/network
interface)
Access/core interface: SN (Service node interface)
or:
# NNI: Network-to-Network Interface
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Terminology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
Maximizing bandwidth requires:# Multiplexing: combining information channels
# De-multiplexing: recovering original signals
3 basic techniques:# FDM, TDM and CDM
3 ways can be combined:# FDM and TDM
# Time-division Duplex:time slots alternate signal directionRequires guard tone to compensate for propagation
delay
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Transmission Equipment
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Data Transmission Equipment
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
Multiplexing:
Channel bank: combine analog voice
signals using FDM (analog) or TDM (digital)
Multiplexer: device that combines digital
channels into a single TDM channel
FDM
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
Remember: if multiplexer determines rate and time
of processing: synchronous
Statistical multiplexing
Inverse multiplexing
T-1/E-1 Carrier
Original form:
# Channel bank multiplexing (24/31 voice to 24/31, 64Kbps
PCM)
# Octet multiplexed to 1.544 /2 Mbps over 4 wires
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
T-1/E-1:
# DS-1 is the speed designator
# Components
PBX to CSU to repeaters to CO
2-pair copper wire
AMI signaling
Max 50 miles (jitter)
Repeaters at 3000ft from CO and customer premises
6000ft. From repeater-repeater
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
1st stage of multiplexing:
Convert voice/modem to digital pulse
# PCM (sampling) 64Kbs base 125uS sample
# 24 channel PCM (DS-1): (24) 8-bit samples each
125uS
# Compress-LPF-sample (PAM)-A/D(PCM)-mix with 23
more-convert binary to AMI at 1.544 Mbps
# 24-channel frame uses 1st bit of every frame for frame
(odd) and Multiframe (even) alignment
Multiframe is 12 frames
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
PDH multiplexing: Plesiochronous digital hierarchy: (still in common use)
# Plesio = almost, close
# Synchronous multiplexers:Tributaries that have the same frequency AND each
are synchronized to a common clock
# Plesiochronous multiplexers:Tributaries have same nominal frequency and no
common clock
Drawback: no easy way to demultiplex channels (add/drop) between major points
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Multiplexers
PDH multiplexing: Plesiochronous Digital
Hierarchy:
# 24 DS-0’s multiplexed=DS-1 (24 channels):
First order multiplexing
# (4) DS-1’s multiplexed=DS-2 (96 channels):
2nd order multiplexing
# (7) DS-2’s multiplexed=DS-3 (672 channels):
3rd order multiplexing
# (6) DS-3’s multiplexed=DS-4 (4032 channels)
4th order multiplexing
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
What is the xDSL
Is the Digital Subscriber line
xDSL are dedicated, point-to-point, public network
Multiple forms of data, voice, and video
Carried over twisted-pair copper wire
Supporting high-speed Internet/intranet access
xDSL are - ADSL, R-ADSL, HDSL, SDSL, and VDSL
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
Is the ADSL ? Is Asymmetric Digital Subscriber Line
It allows more bandwidth downstream
Than upstream from the subscriber
Always on access (which eliminates call setup)
Users of applications download much more information than they send.
Downstream, supports between 1.5 and 8 Mbps
Upstream, is between 640 Kbps and 1.54 Mbps
Provide 1.54 Mbps transmission up to 5.5Km over one-wire pair.
Optimal of 6 to 8 Mbps of 3 to 3.6 Km on 24 AWG wire.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
Is the R-ADSL
Is Rate-Adaptive Digital Subscriber Line
Operates within the same rates as ADSL
Dynamically to varying lengths and
qualities of twisted-pair local access lines.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
Is the HDSL
Is High Bit-Rate Digital Subscriber Line
HDSL technology is symmetric
Providing same bandwidth upstream&
downstream
Speed 1.544 Mbps over two pairs
Speed 2.048 Mbps over three pairs
HDSL’s 3.5 to 4.5 Km operating distance
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
Is the SDSL
Is Single-Line Digital Subscriber Line
Like HDSL, SDSL supports symmetrical
Single copper-pair wire
Maximum operating range of 3 km.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
Is the VDSL
Is Very High Bit-Rate Digital Subscriber Line
Technology is the fastest xDSL
Supporting a downstream rate of 13 to 52 Mbps
Upstream rate of 1.5 to 2.3 Mbps
Single copper-pair wire
Operating distance is only 1,000 to 4,500 feet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
xDSL Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Public Switched Telephone Network (PSTN)
Originally designed for telephone service
Also called plain old telephone service (POTS)
Dial-up connection uses a PSTN or other line to
access a remote server via modems at both the source
and destination
PSTN includes:
Central offices
Long-distance carriers
Points of presence
Subscriber wiring &
equipment
Demarcation point
Local loops
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Public Switched Telephone Network (PSTN)
FIGURE - Typical PSTN connection to the Internet
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Public Switched Telephone Network
Central office
Lines
Voice digitization
Numbering
Services
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Telephone Set
Transmitter
Analog signal
Receiver
Sidetone
Switchhook
On-hook and off-hook
Dialing
Rotary dial
Dual-Tone-Multi-Frequency (DTMF)
Ringing
Call setup time
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Central Office EquipmentManual switching
Electromechanical switching
Electronic switching# Reliable
# One total failure in 40 years
# Quite & efficient
# Less Labor costs with higher skill levels
FunctionsAT & T dynamic non hierarchical routing (DNHR)
# direct, redundancy, and alternate routing
# Maximum 4 toll office
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Central Office Hierarchy
Class 5: local central office
Tandem office
Class 4: toll center
Class 3: primary center
Class 2: sectional center
Class 1 regional center
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Lines
Local loop (pair of copper wires: tip and ring)
Drop wire
Distribution cable
Feeder cable
Trunk
Copper wire
Coaxial cable
Microwave radio
Fiber optic cable
Internet line usage problem
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Voice Digitization Bandwidth
DS-0 with 64,000 bits/sec
T-1 with 24 Ds-0
Adaptive differential pulse code
modulation (ADPCM)
Need half of bandwidth for PCM
Used for voice compression with less
quality
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Telephone Numbering
9 geographic zones in the entire world
Composition
Access code, carrier’s code,
Zone and country code
Area/city code
Exchange code
Subscriber code
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Telephone Services - I
Types of calls
Local calling
Long distance calls
International calls
Operator services
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Telephone Services - II
Calling card calls
Discounted calls
800 or 888 service
Geographic: interstate, intrastate,
international (Universal International
Freephone Numbering -UIFN)
Call direction: in, out, or both
900 service
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Telephone Services - III
Software defined network (SDN)
Foreign exchange (FX) lines
Integrated Services Digital Network (ISDN)
Selection criteria for telephone service
Time
Duration
Number
Location Usage pattern
Usage pattern (busy hour)
1-5% (Blocking) grade service level
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Dialup/ISDN Technology
Is ISDN
Integrated Services Digital Network (ISDN)
ISDN the digitization of the telephone
network
Permits voice, data, text, graphics, music,
video, and other
Is the Dialup Digital Network.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Dialup/ISDN Technology
ISDN Devices
Terminal adapters (TAs),
Network termination (NT)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Dialup/ISDN Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Dialup/ISDN Technology
ISDN Service Type
ISDN Basic Rate Interface (BRI)
# Offers two B channels and one D channel
(2B+D).
# BRI B-channel service operates at 64 kbps
# BRI D-channel service operates at 16 kbps
ISDN Primary Rate Interface (PRI)
# 30 B channels plus one 64-kbps D channel
# Total interface rate of 2.048 Mbps.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Data Networks
Digital lease at n x 64 Kbps
Dedicated High Speed access to internet
On-line transactions
Audio/Video - conferencing
Virtual Private Network (VPN)
Internetworking (connection Local Area
Networks - LANs)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Data Networks
DDN FeatureVery high reliability and data security
Fully-managed network service
Predetermined flat rate charging
Customer manageable VPN
Single point of contact
Guaranteed Quality of Service (Qos)
Burst Excess (BE) opportunity
Multi service platform
Wide range of service portfolio
High-speed access
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Data Networks
LAN
Customer
Corporate Head Office
Copper
Lines
Router
Customer
Branch Office
ETC
Public Data Network
Customer
Branch Office
Copper
Lines
Router
LAN
DTU
LAN
Copper
Lines
Router
DTU
WAN
Cloud (LL
Service)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Data Networks
ETC
Public Data Network
Customer
Branch Office
Copper
Lines
DTU
Router
LANDTU
Router
LAN
ISP
INTERNET
Customer
Branch Office
WAN
(Frame Relay)
Copper Lines
DTU
Router
LAN
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Digital Data Networks
Customer
Branch Office
NON ISDN Telephone
ISDN
Switch
NT1
ETC
Digital Data Network
ISDN PRI
ISDN TERMINALISDN BRI
INTERNET
ISP
Customer Head Office
NT1
LAN
TA
NT1
ISDN Telephone
WAN
(ISDN SERVICE) TA
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Frame-Relay Technology
IntroductionFrame Relay is a high-performance WAN protocol
Operates at the physical and data link layers of OSI
Is Packet-switched networks
Two techniques are packet-switching technology# Variable-length packets
# Statistical multiplexing
Frame Relay is a Layer 2 protocol suite
By CCITT Standard
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Frame-Relay Technology
Frame Relay Devices
Frame Relay WAN following two categories
# Data terminal equipment (DTE)
# Data circuit-terminating equipment (DCE)
DTE generally are
# personal computers, routers, and bridges
DCE are carrier-owned internetworking
# DCE equipment is to provide clocking
# Switching services in a network
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Frame-Relay Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Frame-Relay Technology
Frame Relay Components
Frame Relay Virtual Circuits
# Switched Virtual Circuits
# Permanent Virtual Circuits
Data-Link Connection Identifier
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Frame-Relay Technology
Frame Relay Local Management Interface
Local Management Interface (LMI)
Is set of enhancements to Frame Relay
specification
LMI addressing extension gives Frame
Relay data-link connection identifier (DLCI)
values
synchronization Frame Relay DTE and DCE
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Frame-Relay Technology
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Switching
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Background
ITU uses the words “Transfer Mode” to describe a technique that covers the aspects of transmission, multiplexing, and switching of information signals.
The Asynchronous Transfer Mode (ATM) is the ground on which Broadband ISDN (B-ISDN) is built.
ATM is used in the implementation of many networks worldwide for the transport of voice, data, and video information signals (multimedia).
Key concepts: Traffic-type prioritization
Statistical multiplexing
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Defining ATM
ATM is a specific Packet Oriented Transfer Modebased on Asynchronous Time Division Multiplexingwith fixed length packets called Cells.
Each ATM cell is 53 bytes consisting of a Header and an Information Field (5 +48 bytes respectively).
The information field is carried transparently through the network (no processing or error check).
The header is used to identify cells belonging to the same virtual channel and to perform the appropriate routing.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Transmission Bandwidth Efficiency
h =Number of information bytes
Number of information bytes + number of overhead bytes
The transmission bandwidth efficiency is determined as:
48 48 444555
100
paddingHeader Field
Information Field
Information
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Numerical Example
X Number of useful information bytes to transmit
L Information size of the packet in bytes
H Header size of the packet in bytes
For an information packet length of 100 bytes:
is rounded up to next integer HL
L
X
X
h
L
X
628931.0
5483
100
h
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Another Example
HL
L
h
480.90566
48 5h
For an information packet length of 48 bytes:
For an information packet length of 4800 bytes:
4800
0.90566100 48 5
h
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Transmission Bandwith Efficiency
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 200 400 600 800 1000
Information Bytes
Eff
icie
nc
y
ATM Cell Efficiency
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Switching Networks
ATM Standard
User-to-Network Interface (UNI) 2.0
UNI 3.0
UNI 3.1
UNI 4.0
Public-Network Node Interface (P-NNI)
LAN Emulation (LANE)
Multiprotocol over ATM
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Switching Networks
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Switching Networks ATM Physical Interface Rates
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Switching Networks
ATM Devices and Network Environment
ATM Devices
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Switching Networks
ATM Devices and Network Environment
ATM Network Interfaces
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Communication Path
OSI Reference Model
Application
Presentation
Session
Transport
Network
Data Link
Physical
Application
Presentation
Session
Transport
Network
Data Link
PhysicalBits
F A C Data Unit ( I Field ) FCS F
AP DataPH
Data UnitSH
Data UnitTH
Data UnitNH
AP DataAH
AP DataAP “X” AP “Y”
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
B-ISDN Protocol Reference Model (PRM)
Physical Layer
ATM Layer
Adaptation Layer
Higher Layers Higher Layers
Management Plane
Lay
er Man
agem
ent
Control Plane User Plane
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The ATM Protocol Stack
Physical Layer
ATM Layer
ATM Adaptation Layer
ITU-T Rec. I.150, I.361, I.362, and I.363.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Physical Layer
(e.g. SDH)
SDH: Synchronous Digital Hierarchy
ATM: Asynchronous Transfer Mode
AAL: ATM Adaptation Layer
CS: Convergence Sublayer
SAR: Segmentation and Reassembly Sublayer
SSCS: Service Specific Convergence Sublayer
CPCS: Common Part Convergence Sublayer
ATM Relationship to OSI Model
Data Link Layer
(AAL & ATM)
Network Layer
(Client)
ATM
AAL SAR
CS CPCS
SSCS
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Network Interfaces
CA UNI UNINNI
NNI NNI
B
UNI
UNI: User-Network Interface
NNI: Network-Node Interface
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Virtual Channels & Paths
Virtual Channel Connections (VCCs) are the basic switching units between end users on the network.
VCCs are also used for control signalling and network management functions.
Each VCC is capable of carrying a variable-rate full-duplex flow of cells.
VCCs between the same two points along a network are grouped into virtual path connections (VPCs).
VPCs are in turn multiplexed along a physical medium.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Transmission Path
VP
VP
VP
VC
VC
VC
VP
VP
VP
VC
VC
VC
VC,VP, and Transmission Path
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VCC Structure
VCC
VP Link VP LinkVP Link
VP Switch VP Switch
VPC VPC
VC Switch
User 1 User 2
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VP Switch
Virtual Path Switching
VCI 1
VCI 2
VCI 5
VCI 6
VCI 3
VCI 4
VPI 1
VPI 2
VPI 3
VPI 4
VPI 5
VPI 6VCI 1
VCI 2
VCI 5
VCI 6
VCI 3
VCI 4
VCI: Virtual Channel Identifier
VP: Virtual Path
VPI: Virtual Path Identifier
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VC/VP Switching
VP Switch
VCI 1
VCI 2 VCI 3
VCI 4
VC Switch
VCI 1
VCI 2
VPI 1
VPI 4 VPI 5
VPI 2
VPI 3
VCI 1
VCI 2
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Service Categories
Constant Bit Rate (CBR)
Variable Bit rate Real time (rt-VBR)
Variable Bit Rate non-real time (nrt-VBR)
Available Bit Rate (ABR)
Unspecified Bit Rate (UBR)
The concept of dynamic bandwidth allocation
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The ATM Physical Layer
Transmission Conversion
( TC )
Physical Medium
( PM )
PHY
ATM
AAL
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Physical Layer Functions
Physical Medium (PM):Bit transmission capability, including bit alignment,
Line coding, Scrambling/descrambling, and
If necessary, electrical/optical conversion
Transmission Convergence (TC):Generation and recovery of transmission frames,
Transmission frame adaptation,
Cell delineation,
HEC sequence generation, and
Cell rate decoupling
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
PM Standards
Physical media standardised by the ATM
Forum include SDH/SONET, PDH, FDDI,
and xDSL.
The transmission media include twisted
pair, coaxial, multi-mode and single-
mode fibre.
ITU-T standards SDH (G.707, G.708,
G.709) and PDH (G.703).
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The ATM Layer
Physical Layer
ATM Layer
ATM Adaptation Layer
The functional characteristics of the ATM layer is included in ITU-T Rec. I.150.
The detailed specification is in ITU-T Rec. I.361.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Layer Functions
The characteristic features of the ATM layer
are independent of the physical medium.
The ATM layer performs the following
functions:
Cell Multiplexing
Cell Demultiplexing
VPI and VCI Translation
Cell Header Generation and Extraction
Generic Flow Control (GFC) at UNI
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Cell Structure
Information Field
48 octets
Header
5 octets
8 7 6 5 4 3 2 1
1
.
5
6
.
.
.
53
ATM Cell
53 octets
Bit
Octets are sent to line in an increasing order (i.e. octet 1, 2, ... etc.)
Within an octet, the bits
are sent in a decreasing
order starting with bit 8.
MSB
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
UNI Cell Header
HEC
CLPPTVCI
VCI
VCIVPI
VPIGFC
CLP Cell loss priority
GFC Generic flow control
HEC Header error control
NNI Network-node interface
PT Payload type
VCI Virtual channel identifier
VPI Virtual path identifier
UNI User-network interface
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
NNI Cell Header
HEC
CLPPTVCI
VCI
VCIVPI
VPI
CLP Cell loss priority
HEC Header error control
NNI Network-node interface
PT Payload type
VCI Virtual channel identifier
VPI Virtual path identifier
UNI User-network interface
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
VPI / VCI
Virtual Path Identifier / Virtual Channel
Identifier
Local only to each link
Will change as cell passes through switch
Index into lookup tables setup at
connection time
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Payload Type
3 bits
bit 1
0 = user cell
1 = management cell
bit 3 in user cells
signalling bit
used to signal end of datagram in AAL5
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Cell Loss Priority
1 bit
Switch must drop CLP=1 cells before
CLP=0 cells
Can be set by network
non-conforming cells
Can be set by application
lower priority cells
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Header Error Control
Cyclic Redundancy Check
Calculated over 4 byte cell header
Can correct single bit and detect large
class of multiple bit errors
Recalculated at each hop in the ATM
network
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The ATM Adaptation Layer
Physical Layer
ATM Layer
ATM Adaptation Layer
The functions the ATM Adaptation Layer are specified in ITU-T Rec. I.362 and I.363
(the latter is more detailed).
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
AAL General Functions
Adaptation of the ATM layer services to the higher protocol layers.
Mapping of the user services / control / management PDUs into the information field of ATM cells of a VC and vice versa.
Exchange of information between peer AAL entities.
Consists of two sublayers, SAR (segmentation & reassembly) and CS (conversion sublayer).
Different types of AAL to suit particular traffic: AAL 1, AAL 2, AAL 3/4, AAL 5
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Connection
-lessConnection Oriented
VariableConstant
Not requiredRequired
AAL Service Classifications
Class DClass CClass BClass A
Connection mode
Bit rate
Timing relation
between source and
destination
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Examples of Service Classes
Class A
circuit emulation (e.g. 2MB, 34MB data links),
digitised voice, or constant bit rate (CBR) video.
Class B
variable bit rate (VBR) video and audio.
Class C
connection-oriented data transfer.
Class D
connectionless data transfer.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
AAL Architecture
ATM: Asynchronous Transfer Mode
AAL: ATM Adaptation Layer
CS: Convergence Sublayer
SAR: Segmentation and Reassembly Sublayer
SSCS: Service Specific Convergence Sublayer
CPCS: Common Part Convergence Sublayer
Physical Layer
ATM Layer
SAR
CPCS
SSCSCS
AAL
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Functions Performed by AAL
Segmentation and reassembly of user information,
Handling of cell delay variation,
Handling of cell payload assembly delay,
Handling of lost and misinserted cells,
Source clock frequency recovery at the receiver,
Recovery of the source data structure at the receiver,
Monitoring of AAL-PCI for bit errors as well as handling those errors, and
Monitoring of the user information field for bit errors and possible corrective actions.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SAR Sublayer
At the transmitting side,
segmentation of the higher layer PDUs for insertion into the ATM cells information fields.
At the receiving side,
reassembly of the ATM cells information fields into higher layer PDUs.
The information field of an ATM cell being 48 octets.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
User Data O/P User Data I/P
Segmentation
Reassembly
Transmit Side Receive Side
User Application
AAL
ATM Layer
Physical Layer
ATM
PHY
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Conversion Sublayer
CS is service dependent that interfaces
with the the higher layer via a special
Service Access Point (SAP).
Different SAPs for higher layers can be
derived using different combinations of
SAR and CS.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
AAL
ATM
PHY
User Application
SAP
Service Access Point
CSSAR
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
ATM Forum Contact
Worldwide Headquarters
2570 West El Camino Real, Suite 304
Mountain View, CA 94040-1313
+1.650.949.6700 Phone
+1.650.949.6705 Fax
Europe Office
Av. De Tervueren 402
1150 Brussels, Belguim
+32.2.761.66.77 Phone
+32.2.761.66.79 Fax
Asia-Pacific Office
Hamamatsucho Suzuki Building 3F
1-2-11, Hamamatsucho, Minato-ku
Tokyo 105-0013, Japan
+81.3.3438.3694 Phone
+81.3.3438.3698 Fax
Web site
www.atmforum.com
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
SDH & SONET
What is SDH/SONET ?
# Standard interface developed for the public network
# Multiplexing standard for optical fiber transmission
SONET = Synchronous Optical Network
# Refers to the system used within the U.S. and Canada
SDH = Synchronous Digital Hierarchy
# International community term (ITU-T recommendtions)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
SDH goalsGoals
# Make it possible for different carrier to interwork
# Unify the U.S., European and Japanese digital system
# Provide a way to multiplex multiple digital signal togethers
# Provide support for operations, administration, and maintenace
Characteristics# Use single master clock to synchronize
# Bit stream can be a added or extracted directly
# Basic transmission rate = 155.52 Mbps
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
Synchronous Digital Hierarchy of
Layer Model
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SDH/SONET Switching Networks
Container (C-n)
Is provided for each signal to be transport.
Virtual Container (VC-n)
Is made up from the thus container formed
together.
Tributary Unit (TU-n)
Addition a pointer indicating signal for VC-n.
Administrative Unit (AU-n)
Turn collection together into a VC and plus section
overhead for transport.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Elements
Nonstandard, Functional NamesTM: Terminal MuxADM: Add-Drop MuxDCC: Digital Cross Connect
(Wideband and Broadband)MN: Matched NodeD+R: Drop and Repeat
ADMTMDS1s
DS1s
MN MN
MNDCC
D+R
D+R
D+RMN
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Topology Building Blocks
DCC
ADM
ADM
ADM
DCC
ADM
ADM
ADM 2 Fiber RingEach Line IsFull Duplex
DCC
ADM
ADM
ADM 4 Fiber RingEach Line IsFull Duplex
DCC
ADM
ADM
ADM
Uni- vs. Bi-Directional
All Traffic Runs Clockwise, vs Either Way
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Technology Relationships
Synchronous Digital Hierarchy (SDH)
International Diffs - Terms, OH Fields
Rates: STS-N -> STM-N/3 For N>=3
SDL Proposal
Fix HDLC For High Speed Use
Pt-Pt Links Without SONET Overhead
WDM/DWDM:
More Capacity - Optical Routing For Redundancy
No Access To Lower-Level (I.e. DS1 Signals)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
References
Telcordia (Bellcore) GR-253-CORE
ANSI T1.105 and T1.106
ITU-T G.707 and G.783
SONET, Walter J. Goralski, McGraw-Hill
Series on Computer Communications
RFC-1619 and Successor http://search.ietf.org/internet-drafts/draft-ietf-pppext-pppoversonet-update-
04.txt
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 7
Computer Networking
Design Concept
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
Networking Design Structure
Option of Networking Design
Communication Noise System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Overview of Planning
Overview of planning and design
guidelines.
Understanding Basic Internetworking
Devices
Identifying & Selecting Internetworking
Capabilities
Identifying & Selecting Internetworking
Devices
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Understanding Basic Internetworking Devices
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
Choosing Internetworking Reliability
Options
Redundant Links Versus Meshed
Topologies
Redundant Power Systems
Fault-Tolerant Media Implementations
Backup Hardware
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying & Selecting Internetworking
Capabilities
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Identifying and Selecting Internetworking
Devices
Hubs (concentrators)
Bridges
Switches (Layer 2 or Layer 3)
Fast-Ethernet
Gigabit or ATM
Router
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Sample Networking Design
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Sample Networking Design
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Sample Networking Design
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Sample Networking Design
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Communication
Noise System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Noise Types
Thermal Noise
Inter-modulation Noise
Crosstalk Noise
Impulse Noise
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Noise Types
Thermal noise
Results from thermal agitation of electrons in
a conductor.
It cannot be eliminated,
Depends on the…
temperature,
bandwidth,
uniformly distributed across the frequency
spectrum
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Noise Types
Inter-modulation noise
Results when different frequencies same transmission media
Unwanted signals often appear at frequencies
Differences of the two frequencies
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Noise Types
Crosstalk noise
Results from unwanted coupling between signal paths.
Hearing another conversation (faintly) on a telephone connection
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Noise Types
Impulse noise
Electrical Power Surge,
Short lived disturbances Signaling,
Arrester lightning,
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 8
Computer Network
Management System
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
Introduction to Network Management
Overview of NM Protocol
ICMP – PING
SGMP
HEMS
CMOT (CMIP over TCP/IP)
SNMP SNMP v1, v2 and V3
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Introduction to
Network Management
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Session coverage
Network Management Requirements
Entities in Network Management
Architecture issues in NM
Sample applications
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Why NM?
Multitude of Network elements
Heterogeneity of Network elements
Geographical spread of network
Managing network applications
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Using NM for
Network fault monitoring
Performance monitoring
Network accounting
Load and usage statistics
Network Provisioning
Configuration management
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Network Elements
Virtually everything that can be connected to
network or can be interfaced with the system
Routers
LAN/WAN Switches
Modems
Printers
Servers
Applications
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI Functional Areas
Fault Management
Accounting Management
Configuration Management
Security Management
Performance Management
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
NM reports
No: of links up/down on a specific router
Amount of throughput for a given link
No: of mails pending for delivery with mail server
No: of process running on the server
Routing table in the core router
And much more………..
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
How…?
Using an Open standard and
extensible protocol
Using a standard and extensible way
information base to store and retrieve
information
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Throughput
Packet loss
Time Delay
Link Up/Down
Service running
No: of request
Information Base
Node Info.
No: of links
Link address
Devices attached
Static Information
Dynamic Information
Statistical Information
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Management strategies
Distributed system – Split up the
network and run different management
systems
Centralized – Most applications run on
one machine
Hierarchical – A combination of both
centralized and distributed.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
NM Entities
Monitoring Appln
Manager Function
Monitoring Appln
Manager Function
Agent function
Managed Objects
Agent function
Managed Objects
Monitoring Agent
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
NM Entities
Managed objects – Represents the resources and the information base contained
Agent function – Application that gathers monitors and gathers information about managed objects
Manager function – Provides monitoring and analysis of network resources
Monitoring agent – Generates summaries and statistical analysis. Part of Manager
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Entities Interaction
Pull information from the devices
Push information to Manager
Trade-off analysis
Protocol overhead in pull and push
Computational and processing overhead at nodes
Robustness to network conditions
Response to changing network conditions
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Overview
of
NM Protocols
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Evolution
ICMP – PING
SGMP
HEMS
CMOT (CMIP over TCP/IP)
SNMP SNMP v1, v2 and V3
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
NM Standards
IETF Standards (Operations and
Management)
ISO Standard (CMIP)
IEEE Standard
OMG Standard for NM
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
TMN Process
OS1
OS2OSn
Data Communication Network
Xchange Tran Eq HFC EPAX Telephone
OS – Operations Systems
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI - CMIP
GET
SET
CREATE
DELETE
NOTIFY
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI
App. Service Elements (ASE) and protocols
Define service primitives, protocol and PDU for management operations
CMISE (Common Mgmt. Info. Service Element)Defines service elements used in communication
between service providers and users# Management Notification – reporting of an event
# Management Operation – define operation primitives
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
OSI
CMIP (Common Management Information Protocol)
Used by CMISE
Receives primitives from CMISE
Constructs Application PDU
Sends APDU to peer CMIP user
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
IP Management
SNMP Manager
UDP/IP
DLC Layer
SNMP Manager
UDP/IP
DLC Layer
Network or Internets
Management Process
Managed Resources
Managed Objects
SNMP Manager
SNMP Agent
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SNMP Protocol
Application entities exchange messages using UDP datagrams
Supports other transport mechanisms also
Permitted access mode on variables are Read and Read Write
Messages are encoded using BER
Allows access to objects defined in MIB.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
SNMP
Agent
UDP
IP Layer
DLC Layer
TCPSNMP
Agent
UDP
IP Layer
DLC Layer
TCP
SNMP
Agent
UDP
IP Layer
DLC Layer
TCP
MIB Store
Agent
SNMP
UDP
IPDLC Layer
Managing Process
Inter-network
Host System
RouterSwitch
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 9
Computer Network
Security Concept
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
NETWORKSECURITY...
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Security and its breaches…
Security a system is secure if it is
Security goals are achieved.
Components behaves as expected on it.
Breaches Interruption - System asset lost , unavailable or
unusable.
Interception - Unauthorized party gains access to asset.
Modification - Tampering with the asset.
Fabrication - counterfeit objects on computing system.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Security Goals and Vulnerabilities
Security Goals
Confidentiality - assets of a computing system accessible only by authorized user.Read only type of access like viewing, printing helps in privacy.
Integrity - modification only by authorized parties.
Precise, accurate, consistent assets.
Availability - assets are accessible to authorized parties.Timely response, fair allocation, fault tolerance, usability, controlled concurrency. (Denial of service attacks.)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
The people involved…
Amateurs - fresh players of the game ,
disgruntled over a -ve work situation.
Crackers - breaking into unauthorized territory
without malicious intent.
Hackers - breaking into unauthorized territory
with malicious intent.
Career Criminals - people in the game for
money and have predefined targets.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Basic Encryption and Decryption
Encryption - process of encoding a message so that its meaning is not obvious.
Decryption - process of decoding the encrypted message.
Cryptography - Hidden writing, which conceals meaningful text.
Cryptanalyst - studies encryption and finds hidden messages.
Cryptanalysis attempt to break a single message. Recognize patterns in encrypted messages to break into
subproblems by straightforward decryption algorithm.
Find weakness in encryption algorithms.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contd…
Encryption with Keys
Encryption DecryptionPlain Text Cipher Text Original Text
Encryption Key (Ke)
(Asymmetric Cryptosystem)
Decryption Key (Kd)
Encryption with Keys
Encryption DecryptionPlain Text Cipher Text Original Text
Key
(Symmetric Cryptosystem)
Encryption DecryptionPlain Text Cipher Text Original Text
Encryption
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Encryption
Substitutions - one letter x-changed for other.
Monoalphabetic Ciphers.
# Caesar Cipher
Example: Plaintext:ABCDEFGHIJKLMNOPQRSTUVWXYZ
Cipher :DEFGHIJKLMNOPQRSTUVWXYZABC
Polyalphabetic Ciphers.
# Frequency distribution reflects the underlying letters.Table for Odd Positions
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A D G J M P S V Y B E H K N Q T W Z C F I L O R U XTable for Even Positions
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
N S X C H M R W B G L Q V A F K P U Z E J O T Y D ITable for Odd Positions
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contd…
Transposition - letters of message rearranged.GOAL - Diffusion
Example:
C1 C2 C3 C4 C5
C6 C7 C8 C9 C10
C11 C12 etc.
The resulting cipher text will be
C1 C2 C3 C4 C5
C6 C7 C8 C9 C10
C11 C12 etc.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Authentication in Distributed Systems
Kerberos
User
U
Kerberos
Server
Ticket Granting
Server
1. U’s Identity
Session key
SG
Ticket TG
2. Encrypted under
Password
Session
key SG
2. Encrypted under
KS-TGS Key
Initiating a Kerberos Session
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contd..
Obtaining a ticket to access a file
User
U
Ticket Granting
Server
1. Request to Access
File F
2.Encrypted under
TGS - F Key + SF
Ticket to File Server
to access File F + SF
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Why Kerberos is not the perfect Answer?
Kerberos requires the availability of continuous
trusted “Ticket Granting Server ”.
Trusted relationship required between TGS and every
server.
Requires timely transactions.
Subverted workstation can save and later replay user
passwords.
Password guessing works.
Does not scale well.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Firewalls
Process that filters all traffic between a protected or “inside ” network and a less trustworthy or an
“outside” network.
Special form reference monitor.
That which is not expressly forbidden is permitted.
That which is expressly forbidden is not permitted.
Challenge of protecting a network with a firewall is determining the security policy that meets the need of the installation.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Types of Firewalls
Screening Router.
Address
192.19.33.0
Address
144.27.5.3
Address
100.24.4.0
Allow in only A.
Allow out only B , C.
A
B
C
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contd …
Route Screening outside Addresses
Screening
Router
Subnet 100.50.25.x
100.50.25.1 100.50.25.2
100.50.25.x100.50.25.3
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contd …
Proxy Gateway Two headed piece of software.
runs pseudo applications.
Local Area Network
Remote Access
WWW AccessLogging
Remote File
Fetches
Address
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contd …
Guard sophisticated proxy firewall.
Receives PDU’s interprets them passes the through same or different PDU’s.
Screening
Router
Proxy
Firewall
Address
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Comparisons of Firewall types
Screening Router1.Simplest.
2.Sees only address and
service protocol type.
3.Auditing difficult.
4.Screens based on
connection rules.
5.Complex addressing
rules can make
configuration tricky.
Proxy Gateway1.Somewhat complex.
2.Sees full text of
communication.
3.Can audit activity.
4.Screens based on
behavior of proxies.
5.Simple proxies can
substitute for complex
addressing rules
Guard1.Most Complex.
2.Sees full text of
communication.
3.Can audit activity.
4.Screens based on
interpretation of
message content.
5.Complex guard
functionality can
limit assurance.
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Conclusions
Risks are involved in Computing.
Various techniques Encryption, Digital
Signatures, Firewalls, etc can be used
to provide security.
Web security is not a “Win” or “Loose”
there is just a degree to which it can be
realized.
No Solution is a complete solution !!!
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Chapter 10
NOS (Network Operating System)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Contents
NOS Fundamentals
Clients
Server
Client – Server
Linux/Unix Server NOS
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Why a NOS?
Network tools can be added to an operating
system
A key component of the way the system
A network may be viewed as a collection of
computers or as a collection of resources
A NOS to give transparent access to shared
resources
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Networking Fundamentals
Network consists of:Servers – provides services
Clients – requests services
Peers – both requests and provides services
Types of networksServer-centric networks
Peer-to-peer networks
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Networking Fundamentals
Network ServicesFile services
Print services
Message services
Applications services
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Networking Fundamentals
Network Operating System (NOS)Two parts:
# System software that runs on the server
# Client software on each workstation
Examples# Banyan Vines
# Novell NetWare
# Microsoft LAN Manager
# LANtastic
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Client model
What do clients want?
Simple, efficient access to shared resources
Data security (e.g. RAID)
Data integrity (e.g. clustering)
Often uses “directory services” idea
unified resource naming
hierarchical organisation of objects
Improves on “servers and terminals” structure
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Peer-to-Peer model
Cheaper and simpler than client-server model
Supports basic file and printer sharing
May support other resource sharing
Some administration tools
Simple security measures
Good for connecting small numbers of
personal computers together
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Server Systems
Some common client-server systems
Novell Netware
Many of UNIX
Linux (very light-weight UNIX-like NOS)
Windows 2000 Server
Windows NT Server
Windows XP Server
Windows Server 2003
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Server Systems
Novell NetwareFamous for NDS, the Network Directory Services
NDS is a global database of all network resources, hierarchically structured, searchable, secure and robust
Good for lower overheads on servers than Microsoft’s “Active Directory”
Good support for very thin clients
Netware was very well established in large organisations but seems to be losing market share to NT/Win2000 and to UNIX
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Server Systems
UNIX was developed for
Platform independence
Inter-platform compatibility (but see below)
Network interoperability
Bell Labs, the parent company, was not allowed to
sell UNIX (US anti-monopoly laws)
Different groups developed new
About 20 incompatible versions now!
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Server Systems
UNIX has been around on minicomputers and
mainframes since the early 70’s
It is a good server OS for networks with
Rich utility sets – client services, logging,
administration, security, backup, reliability
Enterprise-scale applications (e.g. RDB’s)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Server Systems
Windows NT/2000/XP/2003 Server
Relatively late entry into the corporate server
market
Seen as the least stable and least secure option by
many
Has some advantages – good performance in many
areas, excellent software support
Has a big chunk of the market
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Peer-to-Peer Systems
The common peer networking OS is Windows
Windows 3.11 for Workgroups (1992)Allowed mapped network drives
Allowed directory sharing
Windows 95 (1995)Partially 32-bit, so had protected memory – secure
Supported long file names, printer sharing
Could connect to Novell Netware
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Peer-to-Peer Systems
Windows 98 (1998)
Better support for Novell Netware
Support for Novell’s NDS – Network
Directory Services
Very limited server capabilities
Still almost no security measures
Last of the “Personal Operating Systems”
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Peer-to-Peer Systems
NT Workstation 4.0 (around 1996-1997)
More robust than Windows 9x
Relatively secure log-in procedure
Support for NTFS with built-in file-level security
and access logging
Different types of user (Administrators, Users,
Power Users etc.)
Robust pre-emptive multitasking
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Review of Peer-to-Peer Systems
Windows 2000 (1998-2000)
Adds support for plug-and-play
Adds power management
Improves file system security and has more flexibility
in NTFS
Better support for peripherals than NT4
Windows XP (2001)
Ease of use (but poor compatibility with Win 9x)
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
Conclusion
We have seen
Why Network Operating Systems are key to modern
computer usage
Some Client-Server model concepts
Some Peer-to-Peer model concepts
Operating systems from the past and present with
networking support
A little of the history and development of the NOS
@2006 - 2007 All rights Created by Mr. Sopon Tumchota Contact at.. [email protected]
I Think are you fun,
for
Network learning, and
more in the future.
Good Luck…. See You