Rev. A01 - Belver Brasil · Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 10...
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Transcript of Rev. A01 - Belver Brasil · Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 10...
Ethernet Basics
Rev. A01
What is Ethernet?
Frame, MAC, VLAN, IP
Ethernet and Cable – Where is Ethernet in Cable?
Key Parameters for Ethernet
How to measure these parameters and verify SLA (Service Level Agreement)
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 2
Agenda
What is Ethernet?
3 Confidential & Proprietary Information of VeEX Inc.
bit (b):
smallest unit of data, a bit is a 0 or 1
It is the format in which the data is processed by computers
byte (B):
equals 8 bits; also called octet
used to describe the amount of data on a network or in a file
kilobits per seconds (kbps or kbit/s):
measures the speed of data transfer on a network: bandwidth
megabits per second (Mbps or Mbit/s):
measures the speed of data transfer on a network: bandwidth
4
Bits and Pieces
Ethernet Basics Confidential & Proprietary Information of VeEX Inc.
5
OSI Model
7
6
5
4
3
2
1
Ethernet Basics Confidential & Proprietary Information of VeEX Inc.
Invented by Robert Metcalf at Xerox in 1973 and patented in 1976
Xerox convinced Intel and Digital to join in making products (group called DIX)
IEEE standardized in 1983 (802.3 Ethernet) and ISO standardized in 1989
6
A Little History
Ethernet Basics Confidential & Proprietary Information of VeEX Inc.
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 7
10/100/1000T/1000X
10Base2 10Base5 10BaseT 10BaseF
Media 50-Ohm Coax 50-Ohm Coax Cat 3, 4, 5 UTP,
2 pairs
Multimode Fiber
(Single mode fiber)
Max Segment
length
185 m 500 m 100 m 2,000m
(10,000 m)
Connector BNC AUI RJ45 SC/LC
100BaseTX 100BaseFX 100BaseFX
Media Cat 5 UTP 2 pairs Multimode fiber Single-mode fiber
Max Seg. Len. 100 m 2,000m 10,000 m
Connector RJ45 SC/LC SC/LC
1000BaseT 1000BaseSX 1000BaseLX 1000BaseZX
Media Cat 5E UTP
4 pairs
850 nm
62.5 or 50 µm Multimode
fiber
1310 nm
50 µm Multimode
Or 9 µm Single-mode fiber
1550 nm
Single-mode fiber
Max Seg. length 100 m 500 m (50 µm)
220 m (62.5 µm)
10 km (SM)
550m (MM)
100 km
Connector RJ45 SC /LC SC/LC SC/LC
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 8
Wiring and “Connectors”
SFP (850 nm)
UTP
Unshielded Twisted Pairs RJ45
LC Connector
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 9
Half Duplex vs. Full Duplex
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 10
Auto Negotiation Conflict
Local Device
Advertised
values
Link Partner
Advertised
values
Local Device
Results
Link Partner
Results
Comments
AUTO-NEG AUTO-NEG 100BT/F-DPLX 100BT/F-DPLX Link at max capability
100BT/F-DPLX AUTO-NEG 100BT/F-DPLX 100BT/H-DPLX Problem: Duplex mismatch
100BT/H-DPLX AUTO-NEG 100BT/H-DPLX 100BT/H-DPLX Link ok, but link partner
defaults to H-DPLX
100BT/F-DPLX 100BT/F-DPLX 100BT/F-DPLX 100BT/F-DPLX Valid manual configuration
100BT/H-DPLX 100BT/H-DPLX 100BT/H-DPLX 100BT/H-DPLX Valid manual configuration
100BT/H-DPLX 100BT/F-DPLX 100BT/H-DPLX 100BT/F-DPLX Problem: Duplex mismatch
10BT 100BT - - Problem: No link
10BT/F-DPLX AUTO-NEG 10BT/F-DPLX 10BT/H-DPLX Problem: Duplex mismatch
10BT/H-DPLX AUTO-NEG 10BT/F-DPLX 10BT/H-DPLX Link ok, but link partner
defaults to H-DPLX
10BT/F-DPLX 10BT/F-DPLX 10BT/F-DPLX 10BT/F-DPLX Valid manual configuration
10BT/H-DPLX 10BT/H-DPLX 10BT/H-DPLX 100BT/H-DPLX Valid manual configuration
10BT/H-DPLX 10BT/F-DPLX 10BT/H-DPLX 10BT/F-DPLX Problem: Duplex mismatch
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 11
Ethernet Frame Format
FCS / CRC
DATA
Type / Length
Source
Address
Destination
Address
SFD
Preamble: 7 Bytes
Start of Frame Delimiter: 1 Byte
Destination MAC Address: 6 Bytes
Source MAC Address: 6 Bytes
Data: 46 to 1500 Bytes long
Frame Check Sequence: 4 Bytes
Length of Frame or Type of Data: 2 Bytes
Preamble
64 to
1518
bytes
MAC address = Unique hardware address
associated with each device
6 Bytes long, represented in hexadecimal format
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 12
MAC Address Format
00 - 00 - 00 - FF - FF - FF
Assigned by IEEE to Vendor : 3
Bytes User Value
Source MAC Address = identifies who is sending
the frame
Destination MAC Address = identifies the station
that should receive the frame
Ethernet Frame Data size = 64 to 1518 bytes = 512 to 12144 bits
Overhead = 7 bytes (Preamble) + 1 byte (SFD) + 96 bits (IPG) = 160 bits
Frame rate = Max data rate/(Data size + Overhead)
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 13
Frame Rate vs. Efficiency
Data size
Overhead
per frame
Frames
per
second
Total bits lost
(overhead)
Percentage
of bandwidth
lost
64 Bytes (512 bits) 160 bits 1,488,095 238,095,238 23 %
128 Bytes (1024 bits) 160 bits 844,594 135,135,135 13 %
512 Bytes (4096 bits) 160 bits 234,962 37,593,984 3.7 %
1024 Bytes (8192 bits) 160 bits 119,731 19,157,088 1.9 %
1518 Bytes (12144 bits) 160 bits 81,274 13,003,901 1.3 %
Ethernet
Frame
IPG Ethernet
Frame
Minimum allowed IPG is 96 bit time:
96 nanoseconds at 1000T/X 0.96 microseconds at 100T 9.6 microseconds at 10T
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 14
Hubs, Switches and Routers
Layer 3
Network
Layer
Layer 2
Data Link
Layer
Layer 1
Physical
Layer
Level of Intelligence and Complexity
HUB
SWITCH BRIDGE
ROUTER
Layer 3
SWITCH
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 15
VLAN
IP address is 32 bits (4 bytes) in length
Allows for 4,294,967,296 unique addresses
How many addresses does IPv6 provide?
340, 282, 366, 920, 938, 463, 463, 374, 607, 431, 768, 211, 456
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 16
IP Header
Ethernet and Cable
Where is Ethernet in Cable?
17 Confidential & Proprietary Information of VeEX Inc.
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 18
Residential and Commercial
RAN CE
Generic term for a mobile network node/site, such as a RAN network Controller or RAN Base Station
RAN NC
A single network controller or a site composed of several network elements including:
OSS, WCDMA Radio Network Controller or Synchronization Server
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 19
Cellular Backhaul
Terminology used in the MEF specification
GIWF Generic Inter-working Function
PCP Priority Code Point
PEC Packet based Equipment Clocks
PTP Precision Time Protocol
RAN Radio Access Network
RAN BS RAN Base Station
RAN CE RAN Customer Edge
RAN NC RAN Network Controller
RNC Radio Network Controller
Key Parameters for Ethernet
20 Confidential & Proprietary Information of VeEX Inc.
Determining the layer of testing and the nature of the link under test
Connectivity
Physical connectivity
Layer 2 and up connectivity
Throughput
Burstability
Latency/Jitter
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 21
Key Parameters for Ethernet
Key to know that Layer 1 is properly connected
Without Layer 1, no additional tests will be successful
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 22
Connectivity
Ethernet drops bad packets
Need to know how many frames to be received in order to
provide accurate Throughput
Errors in packets = Drop Packets
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 23
BERT vs. Throughput
Ethernet is bursty
Burst testing verifies ability to transmit burst traffic
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 24
Burstability
Latency is time from A to B
Jitter is variation of time from A to B
Critical for time-sensitive application
(Banking/Trading, VoIP, IPTV)
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 25
Jitter/Latency
How to …
Measure parameters and SLA
26 Confidential & Proprietary Information of VeEX Inc.
Layer 1
Verify Link Up and MDI settings
Verify Speed, duplex and flow control
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 27
Connectivity
Layer 2 and 3
Layer 2, verify MAC connectivity
ARPing the address
Layer 3 connectivity, verify IP
address is valid before doing any
additional test
PING
BER Testing
Familiar concept
Throughput Testing
Better but not complete
All in one RFC2544
Frame loss
Burstability
Jitter
Latency
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 28
And what about T-PUT and others
RFC2544
Various Frame Sizes
All tests in one set of measurements
Provide A to B and B to A results to
identify the direction of the network
having problems (if any)
Asymmetric Network = Asymmetric Testing
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 29
Performing RFC2544
Latency
Jitter
Burst Test
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 30
Performing RFC2544
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 31
Frame Loss
What is Ethernet?
Bits and pieces, the layers, Frame, MAC, IP, VLAN
Ethernet and Cable
Ethernet is everywhere or almost everywhere
The key parameters?
Green Light Red Light is not enough
How to…
Ethernet Basics Confidential & Proprietary Information of VeEX Inc. 32
Summary
Thank you. Any questions?
33 Ethernet Basics Confidential & Proprietary Information of VeEX Inc.