Network topologiesTopology Description Advantage Disadvantage

Star All nodes connect to a single central device Inexpensive & easy If hub fails, network down; maximum nodes = 1024Bus All nodes connect to a common backbone Simple & less cables If backbone fails, network down; both ends must be

terminatedRing Each node is connected to two other device No collisions; less signal degeneration Expensive; difficult to troubleshoot; proprietary

hardwareMesh Each node connects to every other device Redundancy & fault tolerance Expensive; complicated; difficult to troubleshoot

Common networking standardsStandard Description Speed Access Method Topology Media

802.3 Ethernet 10, 100, 1000 Mbps CSMA/CD physical star, logical bus

UTP, STP, fiber optics

802.5 Token ring 4, 16 Mbps Token passing physical star, logical ring

STP

802.11 Wireless networks 1, 11, 54 Mbps CSMA/CA cellular AtmosphereFDDI Fiber Distributed Data

Interface100 Mbps Token passing dual ring Fiber optics

Ethernet specificationsDesignation Cable Type Max Length Speed Connector Topology Standard

10BASE-T Cat3 UTP 100 m 10 Mbps RJ45 star IEEE 802.3i10BASE-FL MMF 2000 m 10 Mbps ST star IEEE 802.3j100BASE-TX Cat5 UTP, Cat5e FTP 100 m 100 Mbps RJ45 star IEEE 802.3u100BASE-FX Micro MMF 412 m (half

duplex)2000 m (full duplex)

100 Mbps (half duplex)200 Mbps (full duplex)

SC star, point-point

IEEE 802.3u

1000BASE-T Cat5e / Cat6 UTP (4 pairs)

100 m 1 Gbps RJ45 star IEEE 802.3ab

1000BASE-CX Twinax STP 25 m 1 Gbps HSSDC star, point-point

IEEE 802.3z

1000BASE-SX Micro MMF 550 m (50u)275 m (62.5u)

1 Gbps SC point-point IEEE 802.3z

1000BASE-LX SMF or MMF 550 m (MMF)5000 m (SMF)

1 Gbps SC, LC point-point IEEE 802.3z

10 GBASE-SR MMF 300 m 10 Gbps 850nm serial LAN

point-point IEEE 802.3ae

10 GBASE-LR MMF 10,000 m 10 Gbps 1310nm serial LAN

point-point IEEE 802.3ae

10 GBASE-ER MMF 40,000 m 10 Gbps 1550nm serial LAN

point-point IEEE 802.3ae

Wireless networking technologiesStandard Data Speed Frequency Transmission Type Topology Range

IEEE 802.11 Legacy 2 Mbps 2.4 GHz FHSS or DSSS Point-point 30 mIEEE 802.11b WiFi 11 Mbps 2.4 GHz DSSS with CCK Point-point 30 mIEEE 802.11a WiFi 54 Mbps 5 GHz OFDM Point-point 30 mIEEE 802.11g WiFi 54 Mbps 2.4 GHz >20 Mbps: OFDM, <20 Mbps: DSSS with

CCKPoint-point 30 m

IEEE 802.11n WiFi 540 Mbps 2.4 GHz MIMO Point-point 50 mBluetooth 2 Mbps 2.45 GHz FHSS Scatternet 10 mInfrared 100 kbps~ 16 Mbps 100 GHz ~ 1000

THzBaseband Point-point LOS 1 m

IEEE 802.16 WiMax 75 Mbps 2 GHz ~ 11 GHz, 66 GHz

BPSK Point-point Cellular 30 km

The Open Systems Interconnect reference modelNo Layer Function Unit Protocols/Services Devices

7 Application network application services and processes data FTP, TFTP, HTTP, SMTP, SMB, NCP, Telnet, NTP, File & Print, DNS

gateway

6 Presentation

encryption, formatting, compression, translation data ASCII, JPEG, GIF, TIFF, MIDI, MPEG, MIME, Quicktime gateway

5 Session establishes maintains, manages network connections and sessions data RPC, ZIP, SCP, SQL, NetBIOS, NFS, ASP, LDAP, SSL, SMB gateway4 Transport end-end error recovery, connectivity, flow control segment

sTCP, SPX, UDP, NBP, NCP. NetBEUI, SCTP gateway

3 Network routing, forwarding of packets; sequencing of datagram packets IP, IPX, ARP, RARP, DHCP, BootP, ICMP, RIP, BGP, OSPF, IPSec

router, brouter

2 Data Link encoding/decoding of packets into bits; frame synchronization, error checking

frames MAC, LLC, PPP, ATM, frame relay, 802.11b/g, L2TP, FDDI

switch, bridge

1 Physical electrical, mechanical, lightwave, radio frequency, media specifications

bits Ethernet, WiFi, Token Ring, BRI, RS232, V.35 hub, NIC, WAP

Physical media typesMedium Description Types Remarks

Twisted pair Consists of multiple insulated wires that are twisted together in pairs to prevent crosstalk

UTP, STP, ScTP Cat3(16MHz), Cat5(100MHz), Cat5e(100MHz), Cat6(250MHz)

Coaxial cable Consists of a center conductor surrounded by a plastic jacket with braided shield

75Ω, 50Ω RG-58 (thinnet), RG-8(thicknet), RG-62(ARCnet)

Fiber optic cable

Consists of a center glass core surrounded by glass cladding and other protective materials

SMF , MMF 8~10um(SMF), 50~62.5um(MMF), 125um(clad), EMI immune

Types of media connectorsConnector Description Lock Method Usage Developed by

RJ11 Registered Jack modular connector (6P2C)

snap-in telephone equipments, PBX Bell Telephone Labs

RJ45 Registered Jack modular connector (8P8C)

snap-in twisted pair ethernet, PoE, ISDN, T1, token ring

Bell Telephone Labs

F-type F-type coaxial connector (75Ω) screw-on broadband cable, CATV, CCTVBNC Bayonet Nut Coupling (50Ω) bayonet thin ethernet, RF applications Bell Labs, AmphenolST Straight Tip fiber optic connector bayonet fiber optic ethernet AT&TSC Subscriber/Square Connector snap-in fiber optic gigabit ethernet IBMLC Local Connector (SFF) snap-in fiber optic gigabit ethernet LucentMT-RJ Mechanical Transfer Registered Jack

(SFF)snap-in fiber optic ethernet AMP

IEEE 1394 FireWire (i.Link) snap-in digital devices, consumer electronics Apple, Sony, Samsung, Matshusita, IBM, JVC, …

USB Universal Serial Bus (1.1 & 2.0) snap-in digital devices, computer peripherals HP, Compaq, Lucent, Microsoft, Intel, NEC, Philips

Network connectivity devicesDevice Purpose Operation Remarks

Hub Connects all nodes in a network together; transmissions received in 1 port are rebroadcast to all ports

Layer 1 concentrator (passive), repeater (active), MAU

Switch Connects all nodes/segments in a network together; filters and forwards packets; isolate collision domains

Layer 2 multiport bridge, configure VLANs

Bridge Connects 2 network segments with dissimilar media types; isolate collision domains within a segment

Layer 2 wired or wireless

Router Connects 2 networks with different topologies; maps nodes & routes packets; isolates broadcast domains

Layer 3 Brouter, IOS

Gateway Connects 2 networks with different protocols or technologies; could be hardware or software Layer 4, 5, 6, 7

connection to ISP, PABX

NIC An expansion card installed in a device to connect/interface to the network; particular to media & protocol

Layer 1, 2 PCI, USB, PCMCIA, built-in M/B

CSU/DSU A 2 in 1 device used to connect a digital carrier to the network equipment; provides diagnostics & buffering

- T1, T3; V.35 interface

ISDN adapter

The terminal adapter used to connect to the internet via ISDN technology - BRI TA

WAP A device used to connect mobile PCs to a wired network wirelessly via RF technology Layer 1, 2 infrastructure mode, WiFiModem A device that changes digital to analog signal and vice versa; modulator/demodulator - POTS (V.92), xDSL, cableTransceiver A device that transmits or receives analog or digital signals; allows a NIC to connect to a

different media type- media converter, DIX/AUI

Firewall A stand-alone device or software used to protect networks from spyware, hackers, worms, phising, trojans

- port blocking, packet filtering, proxy server, DMZ

Classful IP addressingClass Range Default Subnet No of Subnets No of

Hosts/Subnet

Class A 1.0.0.0 ~ 126.0.0.0 255.0.0.0 126 16,777,214Class B 128.0.0.0 ~ 191.0.0.0 255.255.0.0 16,384 65,534Class C 192.0.0.0 ~ 223.0.0.0 255.255.255.0 2,097,152 254

Reserved IP address blocksCIDR address

blockDescription Referenc

e0.0.0.0/8 Network or wire address RFC 170010.0.0.0/8 Private network (Class A) RFC 191814.0.0.0/8 Public data network RFC 170039.0.0.0/8 Reserved RFC 1797127.0.0.0/8 Localhost (Loop back address) RFC 1700128.0.0.0/16 Reserved -169.254.0.0/16 Zeroconf , APIPA RFC 3927172.16.0.0/12 Private network (Class B) RFC 1918192.0.2.0/– Documentation and example code RFC 3330192.88.99.0/24 IPv6 to Ipv4 relay RFC 3068

192.168.0.0/16 Private network (Class C) RFC 1918198.18.0.0/15 Network benchmark tests RFC 2544223.255.255.0/24 Reserved RFC 3330224.0.0.0/4 Multicasts (former Class D) RFC 3171240.0.0.0/4 Experimental (former Class E) RFC 1700255.255.255.255 Broadcast -

Physical and logical addressingVersion Length Notation Delimiter Separation Supports Example

MAC 48 bits Hexadecimal Colon (:), Dash (-)

8-bit hexadecimal digits (2 hex)

12x109

combinations00:50:DA:C3:8A:F9

IPv4 32 bits Dotted-decimal Dots (.) 8-bit binary coded decimal digits

4.3x109 addresses 207.142.131.235

IPv6 128 bits Hexadecimal Colon (:) 16-bit hexadecimal digits (4 hex)

3.4x1038 addresses 2001:0DB8:0::0::1428:57AB

Rules of subnettingNo Rule

1 B bits => 2; R bits => 22 Usable subnets created = 2B - 23 Usable hosts per subnet = 2R - 24 Decimal value of the number of bits borrowed = increment of

the subnets

Commonly used well-known portsPort Name Function

20 FTP Reliable transfer of data; uses TCP21 FTP Provides flow control; uses TCP22 SSH Executes command and moves files; remote login protocol; uses TCP23 TELNET Connects a remote computer to a server; uses TCP

25 SMTP Delivers emails between email servers; sending of emails; uses TCP53 DNS Translates hostnames to IP addresses; uses TCP (zone transfers), UDP (queries)69 TFTP Simple transfer of data; uses UDP80 HTTP Opens a browser connection to a webpage; uses TCP110 POP3 Delivers emails between a mail server and client; receiving of emails; uses TCP119 NNTP Views and writes news articles for newsgroups; uses TCP123 NTP Sets computer clock to standard time; uses UDP143 IMAP4 Downloads emails; stores and searches messages from newsgroups; receiving of

emails; uses TCP443 HTTPS Allows browsers and servers to authenticate and encrypt network packets; uses SSL;

uses TCP

Switching type comparisonResource Circuit Switching Packet Switching

Dedicated path? yes noAvailable bandwidth? fixed dynamicCould Bandwidth be wasted? yes noStore-and-forward transmission no yesEach packet follows the same route?

yes no

Call setup required not requiredWhen can congestion occurs? at set-up at every packetCharge? per minute per packet

Network protocolsProtocol Routing Addressing Naming Interoperability

IPX/SPX RIP, SAP, NLSP 12-digit hexadecimal server names only: 64 characters, no special characters; NDS

Windows, Linux

NetBEUI unroutable - NetBIOS or computer names; WINS WindowsAppleTalk version1: unroutable; version2: RTMP 24-bit address version1: NBP; version2: IP naming ethernet: ELAP, token ring: token

talkTCP/IP RIP, OSPF 32-bit address DNS, ARP, RARP Windows, UNIX, Linux, Mac, Novell

Digital transmission hierarchiesCarrier Channels Data Rate Format

T1 24 1.544 Mbps North American

T3 672 44.736 Mbps E1 32 2.048 Mbps

EuropeanE3 480 34.368 Mbps J1 24 1.544 Mbps

JapaneseJ3 480 32.064 Mbps

Optical carriersLevel Data Rate

OC-1 51.84 MbpsOC-3 155.52 Mbps

OC-12 622.08 MbpsOC-24 1.244 GbpsOC-48 2.488 Gbps

xDSL technologiesType Distance Downstream Upstream Characteristic Use

ADSL 18,000 ft 1.544 Mbps ~ 6.1 Mbps 126 kbps ~ 640 kbps Most popular; used for web access and multimedia streaming

SDSL 12,000 ft 1.544 Mbps(US), 2.048 Mbps(EU)

1.544 Mbps(US), 2.048 Mbps(EU)

WAN connection from company network server to phone company

HDSL 12,000 ft 1.544 Mbps (2p), 2.05 Mbps (3p)

1.544 Mbps (2p), 2.05 Mbps (3p)

WAN connection from company network server to phone company

IDSL 18,000 ft 128 kbps 128 kbps Transmits data only; similar to ISDN BRICDSL 18,000 ft 1.544 Mbps <1.544 Mbps Used in home and small business; no splitter; known as

G.liteRADSL n/a 640 kbps ~ 2.2 Mbps 270 kbps ~ 1.1 Mbps Same as ADSLVDSL 4500 ft 1.6 Mbps ~ 53 Mbps 1.5 Mbps ~ 2.3 Mbps ATM networks using fiber optic cable

TCP/IP protocol suiteName Meaning Function

TCP Transmission Control Protocol Enables two hosts to establish connection and exchange network data; connection-oriented; guaranteed

delivery of packetsUDP User Datagram Protocol Enables two hosts to establish connection and exchange network data; connectionless, unreliable, less

overheadFTP File Transfer Protocol Downloads or uploads files between hosts; performs directory operations; also offers authentication securitySFTP Secure File Transfer Protocol Transfer of files with SSH to provide encryption, public key authentication, and file compression; similar to FTPTFTP Trivial File Transfer Protocol Facilitates file transfer between computers; uses lesser bandwidth and faster speed; similar to FTP; used in

firmware downloadingHTTP HyperText Transfer Protocol Transfer files or web pages from web server to client web browser; uses lesser bandwidth and supports both

text and graphicsHTTPS HyperText Transfer Protocol Secure Allows browsers and servers to authenticate and encrypt network packets using SSL; secure version of HTTPSMTP Simple Mail Transfer Protocol Uses a spooled or queued method to deliver or send emailsPOP3 Post Office Protocol version 3 Used to retrieve email files from the email server; can be used with or without SMTPIMAP4 Internet Message Access Protocol

version 4Used to retrieve email files from the email server; similar to POP3 but with added features; supports Kerberos

Telnet Telephone Network A terminal emulation program that connects remote computers to a server; execute a commands using command prompt

SSH Secure Shell A suite of protocols used to log into another computer on the network, execute commands, and secure transfer of files

ICMP Internet Control Message Protocol Provides network layer management and control by sending datagrams and control messages; works with IPARP Address Resolution Protocol Resolves network addresses (IP) into hardware addresses (MAC); uses address resolution cache table built into

every NICRARP Reverse Address Resolution Protocol Uses host MAC address to discover its IP addressNTP Network Time Protocol Sets computer clock to a standard time source usually a nuclear clockNNTP Network News Transfer Protocol Used for the distribution, inquiry, retrieval, and posting of news articles and newsgroup forum messagesSCP Secure Copy Protocol Safe and secure copying of files between a local and remote computer; similar to SFTPLDAP Lightweight Directory Access Protocol A session layer protocol that provides directory services and access to x.500 information directoriesIGMP Internet Group Multicast Protocol A network layer protocol used to report multicast group membership to adjacent routersLPR Line Printer Remote A printer protocol used to print across different NOS platforms

Network services and protocolsName Meaning Function

DNS Domain Name System Translates and resolves IP addresses into host names or the reverseDHCP Dynamic Host Configuration Protocol Allows a client device to request and obtain a unique IP address and other parameters from a server automaticallyNAT Network Address Translation Allows a local network to use one set of IP address for internal or in-house traffic and a different set for external or internet

trafficICS Internet Connection Sharing Connects multiple computers on a local network to the internet through a single connection and IP address; uses NATWINS Windows Internet Naming Service Resolves a host NetBIOS name or computer name into an IP address; used in legacy WindowsSNMP Simple Network Management Protocol Monitors the network and network devices; sends messages to different parts of the network; uses MIBNFS Network File System Permits network users to access and used shared files; allows different computer platforms to share files and disk spaceZeroconf

Zero Configuration Connects networking devices using an Ethernet cable; no configuration or DHCP required

SMB Server Message Block Shares files, directories, and services; message format used by DOS; allows UNIX/Linux and Windows machines to share files

AFP Appletalk File Protocol A file sharing protocol used with TCP/IP to permit non-apple computers to access apple serversLPD Line Printer Daemon Processes LPR print jobs, queues, and prints filesSamba - Provides file and print services to SMB clients; runs on UNIX and LinuxICA Independent Computing Architecture The core of Citrix presentation server that enables Windows or UNIX server to run an application for multiple users

simultaneouslyApache - A popular public domain UNIX-based web server

Remote access protocols and servicesName Meaning Function

RAS Remote Access Service Used for client remote access to a networkPPP Point-Point Protocol Used to establish an internet connection between serial point-to-point links; provides for dial-up connnections to networks

SLIP Serial Line Internet Protocol Used to connect to the internet via a dial-up modem; older, slower, less reliable than PPPPPPoE PPP over Ethernet Uses PPP over Ethernet to connect an ethernet LAN user to the internet using an ADSL or cable modem; users share a

broadband connectionPPTP Point-Point Tunnel Protocol A form of encryption that provides a tunnel for secure connections over the internet; used to create VPNVPN Virtual Private Network A private, secure, point to point connection from a company LAN to the remote users and wireless nodes using the internetRDP Remote Desktop Protocol connects a client to a network via a terminal server and uses authentication to establish connection to run applications and

printers remotely

Security protocolsName Meaning Function

IPSec Internet Protocol Security Provides authentication and encryption over the internet; works with IPv4 and IPv6; used to secure VPNL2TP Layer 2 Tunneling Protocol Supports non-TCP/IP protocols VPN over the internet; combines the best features of PPTP and L2FSSL Secure Sockets Layer Uses a private key to encrypt data that is transferred over the SSL connection; service independent and can secure

different network applicationsWEP Wired Equivalent Privacy Encrypts and protects data packets over radio frequencies; does not offer end-end securityWPA WiFi Protected Access Offers improved data encryption and user authentication using the wireless devices MAC address; uses TKIP encryptionAES Advanced Encryption Standard A cryptographic cipher that uses Rijndael algorithmPGP Pretty Good Privacy An encryption utility based on public key encryption designed to encrypt email transmissions802.1x - Method for passing EAP over both wired and wireless networks; provides authentication services for wireless networks not

using PPP

Authentication protocolsName Function

CHAP Challenge Handshake Authentication Protocol

Uses a hashed algorithm MD5 that provides client response encryption; weak and one-way authentication protocol

MS-CHAP

Microsoft Challenge Handshake Authentication Protocol

Has two versions used in Windows systems that offers more security; version1 not compatible with version2

PAP Password Authentication Protocol The weakest authentication protocol that sends username and password in clear text over the network to be verified by RAS

RADIUS Remote Authentication Dial-in User Service

An industry standard that provides authentication, authorization, and accounting services

Kerberos

- A fully-fledge security system that uses secret key cryptography

EAP Extensible Authentication Protocol A general protocol often used by a wireless devices to connect to a RADIUS server; TLS uses certificates such as smart cards

Routing protocolsName Meaning FunctionRIP Routing Information Protocol Finds the quickest route between two computers; offers a maximum of 16 hops between routers before

deciding that a packet is undeliverableOSPF Open Shortest Path First A descendant of RIP that increases its speed and reliability; much used on the internet; accepts 256 hops

between routersIGRP Interior Gateway Routing

ProtocolA propriety protocol from Cisco that takes bandwidth, latency, reliability, and current traffic load into consideration

EGP Exterior Gateway Protocol A distance vector protocol that uses polling to retrieve routing informationBGP Border Gateway Protocol Used to span autonomous systems in the internet; used at the edge of networks; designed to supersede

EGPNLSP Netware Link Services Protocol A link state routing protocol that was designed to reduce wasted bandwidth associated with RIPRTMP Routing Table Maintenance

ProtocolUsed by Appletalk to ensure that all routers in the network have consistent routing information

Network operating system versionsVendor Releases

Novell Netware 3.x, 4.x, 5.x, 6.xMicrosoft Windows NT, Windows 2000, Windows Server

2003Apple Mac OS X, AppleShare IP

UNIX/Linux SCO ACE, RedHat

Server operating systems basic capabilitiesOperating

System

Client Support Authentication File & Print Services Interoperability

UNIX/Linux multi-user, multitasking; GUI

etc/password; NIS authentication; LDAP LPD/LPR; FAT16, FAT32, NTFS, Ext2, Ext3; NFS

Windows, Linux, Netware, Mac OS

Netware multi-user, multitasking; GUI

user password; keys stored in NDS; eDirectory

FAT16, FAT32, NTFS, NFS, AppleShare Windows, Linux, Netware, Mac OS

Windows multi-user, multitasking; GUI

domain username/password; AD LPD/LPR; FAT16, FAT32, NTFS Windows, Linux, Netware, Mac OS

Mac OS multi-user, multitasking; GUI

kerberos mechanism; keychain; OD UNIX-type file system, AppleShare IP Windows, Linux, Netware, Mac OS

TCP/IP utilitiesUtility Operating System Function Switches

config NetWare displays IP stack configurationifconfig UNIX/Linux displays IP stack configurationwinipcfg Windows 95/98 displays IP stack configurationipconfig Windows NT/2000/XP displays IP stack configuration, release/renew DHCP IP address,

flush/register DNS/all /renew /release /flushdns /registerdns

ping Windows/UNIX/Linux/Netware

verifies end-to-end network connectivity; uses ICMP echo packets –t –a –n –l –f –i –r –v

tracert Windows 2000/XP/2003 traces routes to internet sites based on the number of hops and displays time taken

–d –h –j –w

traceroute

UNIX/Linux traces routes to internet sites based on the number of hops and displays time taken

netstat Windows/UNIX/Linux/Netware

displays protocol statistics and current TCP/IP network connections –a –b –e –r –o –s –n –p

nbtstat Windows/UNIX/Linux/ displays protocol statistics and current TCP/IP network connections –a –A –c –n –r –R –S –s

Netware using NetBIOS over TCP/IParp Windows/UNIX/Linux/

Netwaredisplays and/or modifies IP to physical address translation tables; displays current ARP cache

–a –g –s –N

nslookup Windows 2000/XP/2003 queries a DNS name server; used to troubleshoot DNS and verify DNS resolution

–a –d –t exit

dig UNIX/Linux nslookup equivalenttelnet Windows/UNIX/Linux/

Netwareenables a computer to function as a terminal working from a remote computer

–a –e –f –l –t

netuse Windows NT/2000/XP used to connect to file or print shareTools for network cabling and troubleshooting

Tool Usage

Wire crimper Used to affix an UTP/STP cable to a modular connector or plugPunchdown tool Used to affix several cables to a punchdown block or a patch panel found in wiring cabinetsMedia tester/certifier

Used to test continuity or polarity of cables, trace shorts along the line; can’t be used on live/active wires

Tone generator Used along with a probe to verify cable continuity, identify wiring faults, determine line voltage and polarity; can be used in active wires

Common network implementationImplementati

onPurpose Characteristics/Benefits Remarks

Firewall security Permits/denies public traffic based on various filtering rules; protection from internet threats

ACL, DMZ

Proxy server security, performance A firewall method that caches web content for improved network performance; establish VPN for remote users

web proxy, ip proxy

Antivirus software

security, maintenance Software used to search/remove malicious programs on network computer hard drives; prevents infection

viruses, worms, trojan horses

VLAN security, performance Better bandwidth management; reduced administration costs; well-defined groups; improved network security

static/dynamic; VTP, DTP

Intranet cost, flexibility A private network based on TCP/IP which resides behind a firewall; cheaper, versatile, flexible information sharing

-

Extranet security, versatility Extension of a corporate intranet; exchange data between suppliers/customers; secure corporate purchasing

-

Clustering fault-tolerance, load balancing

A group of redundant mirrored servers; high availability and scalability; minimized network downtime

-

Network security implementationImplementatio

nPurpose Impact on network Remarks

Port blocking intrusion detection slows down firewalls, proxy serversPacket filtering intrusion detection slows down firewalls, proxy serversAuthentication access control none NOS logon serverEncryption data protection slows down IPSec, PKI, PGP,

Kerberos, DES

Characteristics of fault-toleranceItem Implementation

Power UPS, SPS; backup generators, cooling fans, processors; surge suppressor; line conditioners

Link redundancy Backup links: ISDN, dial-up; microwave wireless radios; secondary ISP; clustering

Storage Hardware or software RAID; SCSI hard disks; data warehousingServices Mission critical servers and equipments: gateways, routers,

switches; SAN clusters, MSOSDisaster recovery

Backup/restore schemes; offsite storage: NAS, SAN; hot/cold spares; hot, warm, cold sites

Types of RAIDLevel No of

drivesDescription

RAID 0 2 disk stripping without fault toleranceRAID 1 2 disk mirroring/duplexingRAID 0+1 4 a mirror of stipesRAID 5 3 stripping with parityRAID 10 4 stripe of mirrors

Backup typesType Description Clears archive

bit?Sets to restore

full/normal

backs up all data; longest time to backup Y full only

incremental

backs up files changed or added since the last backup; faster to backup; uses more tapes

Y full + every incremental

differential

backs up files changed or added since the last full backup; faster to restore; uses lesser tapes

N full + last differential

mirror/copy

backs up all data; used to make offsite copies; N -

Types of backup tape drivesDrive Description Capacity Data Transfer Speed

QIC Quarter Inch Cartridge; formats: 3.5”, 5.25” 20 GB, 50 GB 60 kbps, 125 kbpsTravan Enhancement of QIC; formats: TR4, TR5 4/8 GB, 10/20 GB 1 Mbps, 1.83 Mbps

DAT Digital Audio Tape; formats: DDS (Digital Data Storage), DLT (Digital Linear Tape)

40 GB (DDS), 160 GB (DLT)

4.8 Mbps, 20 Mbps

Mammoth An 8mm backup format used in computer systems; AIT (Advanced Intelligent Tape)

10/20 GB, 20/40 GB 3 Mbps, 6 Mbps

Troubleshooting strategyNo Step1 Identify the symptoms2 Identify the affected area3 Establish what has changed4 Select the most probable

cause5 Implement a solution and

action plan6 Test the result7 Recognize the effects of the

solution8 Document the solution and

process

IEEE StandardsStanda

rdDescription

802.1 Internetworking802.2 Logical Link Control (LLC)802.3 Ethernet (CSMA/CD)802.4 Token bus LAN802.5 Token ring LAN802.6 Metropolitan Area Network (MAN)

802.7 Broadband technical advisory802.8 Fiber optic802.9 Integrated voice/data

802.10 Network Security802.11 Wireless Networks802.12 Demand Priority (100VG-Any LAN)802.13 Not used802.14 Cable modem802.15 Wireless personal area network802.16 Broadband wireless access802.17 Resilient packet ring