ethernet technology training

Ethernet Technology Training

Bhavik Joshi

Home of Acterna

Test & Measurement Solutions

www.jdsu.com/acterna

© 2005 JDSU. All rights reserved. JDSU CONFIDENTIAL & PROPRIETARY INFORMATION2

Agenda

OSI Reference Model and Overview

A Brief overview Layer 4 to Layer 7

Ethernet at Physical Layer – Layer-1

Ethernet at Data Link Layer – Layer-2

Examination


OSI Reference Model

The OSI (Open Systems Interconnect) model defines layers in a network.

Understanding the function of each layer is key in understanding data

communication within Local, Metropolitan or Wide networks.

T1, SONET, WDM,

ATM, Frame Relay, PPP

IP, IPX (Novell), ARP, RARP

TCP, UDP

FTP, Telnet, HTTP,

SMTP, DNS

Application

Presentation

Session

Transport

Network

Data Link

PhysicalLayer 1

Layer 2

Layer 3

Layer 4

Layer 5

Layer 6

Layer 7


OSI Vs. TCP/IP Reference Model

Application

Presentation

Session

Transport

Network

Data Link

PhysicalLayer 1

Layer 2

Layer 3

Layer 4

Layer 5

Layer 6

Layer 7

Application

TCP/UDP

IP

Ethernet

Ethernet Phy

Layer 5

Layer 4

Layer 1

Layer 2

Layer 3

TCP/IPOSI


Data Encapsulation

MAC

IP

TCP

SMTPEmail contents

SMTPEmail contents

TCP SMTPEmail contents

IP TCP SMTPEmail contentsFCS

Application:Send an email

Application Layer: Email (SMTP)

Transport Layer: TCP

Network Layer: IP

Data Link Layer: Ethernet

Physical Layer: Transmits bit 0s and

1s on the media


Data De-Encapsulation

MAC

IP

TCP

SMTPEmail contents

SMTPEmail contents

TCP SMTPEmail contents

IP TCP SMTPEmail contentsFCS

Application: Receive an email

Application Layer: Email (SMTP)

Transport Layer: TCP

Network Layer: IP

Data Link Layer: Ethernet

Physical Layer: Transmits bit 0s and

1s on the media


LANs MANs and WANs

LAN – Local Area Network

LANs are widely used to connect computers / workstations in company offices

to share resources (e.g., printers) and exchange information in which network

are restricted in size.

MAN – Metropolitan Area Network

MANs are widely used to connect group of corporate offices which are restricted

into region or city. It is basically bigger version of LAN. e.g., city wide regional

network

WAN – Wide Area Network

WANs are network which connects multiple MAN and LAN in Large

Geographical area e.g., country wide national network


The New Network Architecture

Business

SubscriberService Provider

Transport

IP

IP

• Carries all applications

• Internet Access

• IP VPN service

• Hard QoS and Traffic Engineering

• Better bandwidth utilization/Scalability

• Protection Switching (50ms)

• OAM functions and TDM Support

• Any-to-Any VPN services

• Multicast support with Hard QoS

Residential

Subscriber

Source : Metro Ethernet Forum


Original Ethernet

RG-8 150Ω Coax-500 meters

RG-58 50Ω Coax- 186 (200) meters

UTP


10Mbps Standard

10Base2: Thinwire coaxial cable (50ohm) with a

maximum segment length of 200 meters uses BNC

Connector

10Base5: Thick coaxial cable (50ohm) with a maximum

segment length of 500 meters uses AUI connector

10BaseT: twisted pair wire (CAT5,5e) with a maximum

segment length of 100 meters uses RJ45 connector

10BaseF: fiber optic cable with a maximum segment

length of 2000 meters uses SC/LC connector

Note: 10BaseT means that it operates at 10Mbps

uses baseband signaling on twisted pair.


100Mbps Standard

100BaseTx: CAT5,5e UTP (unshielded twisted

pair) cable covers maximum segment length of 100

meters uses RJ45 connector

100BaseFx MMF: Fiber optic cable covers

maximum segment length of 2000 meters on

Multimode Fiber (850nm) uses SC/LC connetor

100BaseFx SMF: Fiber optic cable covers

maximum segment length of 10,000 meters on

Single mode Fiber (1310/1550) uses SC/LC

connector


1000BaseSX - Short Haul – 275m

1000BaseLX - Long Haul – 550m/5000m

1000BaseZX – Very Long Haul – 80km

• Basic Ethernet Technology but FASTER

• Primarily a Backbone/Server technology

• Although half duplex is supported it is not often implemented

1000BaseT - RJ45 UTP

All 8 wires used

Gigabit Ethernet


1000Mbps / 1GE Standard

1000BASE-SX (850 nm, MMF)

275m w/62.5um multimode, 550m w/50um multimode

1000BASE-LX (1310 nm, SMF/MMF)

550m w/50 or 62.5 um multimode, 5000m w/10um

single-mode

1000BASE-ZX (80km, 1550nm, single mode)

1000BASE-T copper GigE – 100m Copper UTP


Line speeds (Types of Ethernet)

TX

Pair

RX

Pair

GBIC

SFF

TX

Pair

RX

Pair

100BaseFX

X2XFP

10Base-T

1 Gbps 10 Gbps

100Base-T


Physical Layer Data Transfer

Signals are placed on wire or fiber via transceivers

Problem is how to transmit 0’s and 1’s (signal encoding) in

a robust fashion

– Binary voltage encoding

• Map 1 to high voltage

• Map 0 to low voltage

– How are consecutive 0’s or 1’s detected at node?

• Clock synchronization problem

Transmitted signals have a variety of problems

– Attenuation

– Noise

– Dispersion


Gigabit Ethernet Physical Layer

Physical Coding Sublayer– Synchronization

– Transmit

• Performs 8b/10b encoding of MAC for physical layer

transmission

• Generates idle when no data received from the MAC layer

– Receive

• Determines what needs to be sent up to MAC

• Performs 8b/10b decoding of physical layer data to be sent to

MAC

– Performs Auto-negotiation


Gigabit Ethernet Physical Layer

8b/10b Encoding - Each byte from the MAC layer is

encoded into a 10-bit code word for physical layer

transmission

– High bit transition density

– DC Balance

– Separate code groups for signaling

MAC layer

Physical layer

10110011

0110101100

or

0110100011

Rate = 1.0 Gbps

Rate = 1.25 Gbps

8b/10b Encoder


8b/10b Encoding & Decoding

Applies to Gigabit Ethernet over Fiber, 1000BaseX

Based on Fiber Channel FC-1 Standard

Before transmission, each 8-bit byte is translated to a 10-bit code group

Ensure sufficient transitions for clock recovery

Greatly increases the likelihood of detecting any single or multiple bit errors that may occur during transmission and reception of information.

Limits the effective transmission characteristics, such as ratio of 1s to 0s, on the error rate.

Code group decoded back to the original data at the receiver


4 Port Hub

Source

MACDestination

MAC

TX

Pair

RX

Pair

10BaseT

low cost RJ45 UTP

Layer 1 device

Operates in Half Duplex

Collisions, retransmissions, and FCS errors are an

issue

Repeats every received frame

out every other outgoing interface

10Base-T and Hubs


CSMA/CD

Carrier Sense Multiple Access with Collision

Detection

Half-Duplex


CSMA/CD and Collisions


Collision Domain


10BaseT/100BaseT

low cost RJ45 UTP

4 Port Switch

Source

MACDestination

MAC

TX

Pair

RX

Pair

100BaseFX

MM fiber

Don’t repeat signals out all interfaces like a hub

Intelligent device which learns where a device exists on

the network

Reads frames which pass through it

Create a MAC address table

Connects different speed devices

Full duplex, and no collisions

100Base-T and Switches


Switching functions, and MAC address learningTypically functions in Full-Duplex therefore can eliminate Collisions


Access Ports vs. Trunk Ports

Non Tagged FramesAccess ports

Access ports

Access ports

Trunk Ports

Non Tagged Frames

Non Tagged Frames


Bridging Loops

Switch 1

Switch 2 Switch 3


Spanning Tree ( STP )

Switch 1

Switch 2 Switch 3

Blocked


WAN

Router

Router

A Router creates and separates networks

A Router contains the broadcasts with-in the network

By using routers a node needs to know only the device on its local

network, the router takes care of non-local devices

Transmission is based on the destination IP Address

Ethernet MAC Addresses have local significance only

Routers vs Switches


Half Duplex Transmission

SLOW

CSMA / CD

Traffic can be either transmitting or receiving a frame, but it

cannot be doing both simultaneously.

Collision is possible


Full Duplex Transmission

Simultaneous two way transmission

Doubles the Bandwidth

Collision Free Transmission


Auto Negotiation

A process used to establish the link

Each end station advertises capabilities to the other

Each end station will configure themselves to the highest common denominator of capabilities

Key parameters advertised

• Link Speed: 100Mbps / 10 Mbps

• Duplex: Half / Full Duplex mode

• Flow control capabilities

After process is completed, link is established and ready to carry frames, IDLE word transmitted continuously on link

Both devices must have Auto-negotiation enabled or disabled, otherwise a negotiation mismatch will result and link will not be established


Auto Negotiation

Speed, Duplex, Flow Control

Best common parameters negotiated

For proper operation both directly connected devices need to auto negotiate

Auto to Auto = Auto

Auto to Manual = Half-Duplex on the auto side and manual setting on the manual set side

Manual to Manual = Manual


Testing for Auto Negotiation

If the test set is configured for auto-negotiation and connected to an auto-negotiating interface it will show what the capabilities are of the link partner

If the test set is configured for auto-negotiation and connected to a non-auto negotiating link partner it will display a message indicating that it is not receiving auto-negotiation messages

This allows you to determine if the link partner is configured for auto-negotiation, and what it’s capabilities are

Or determine if the link partner is not configured for auto-negotiation

If the test set is configured for auto-negotiation and the test set displays that it has configured itself for half-duplex this may be the result of a duplex mismatch from an auto-negotiating to non auto-negotiating link

It is important to know if the link partner is auto-negotiating or not and if not to be configured to match the manual configuration to obtain valid test results


Flow Control

Used in Full Duplex mode only. A mechanism used to control network

congestion and prevent traffic from being dropped

If Receiver Station is congested it sends a PAUSE frame to the link

partner and link partner will stop data transmission for a short time

Flow control can be enabled or disabled

– If Flow control is disabled and congestion occurs frames will be lost

PAUSE Frames

– Uses a defined MAC control frame format

• Exclusive MAC address, L/T identifier

– Contains a time field that defines PAUSE time

– Receipt of a PAUSE frame causes device to cease transmission for PAUSE time

Station congested

sends PAUSE frame

Station waits before

resuming transmission


Flow Control

1

8

100 Mbps

2

7


Test with Flow Control

2


Ethernet at Data Link Layer

Layer 2

Home of Acterna




Ethernet Frame Format

Same frame regardless of rate (10/100/Gigabit/10GigE LAN)

Variable Frame Size – must have integer number of bytes

64 - 1518 bytes excluding Preamble and SFD

Note:

– Undersized frames (less than 64 bytes) are considered errored

– Oversized frames – Jumbos (larger than 1518 bytes or 1522 with VLAN) are considered valid

Data (46-1500)L/T (2)SA (6)DA (6) FCS (4)SFD (1)Preamble (7)


Ethernet Media Access Control (MAC)

Preamble

– Allows physical layer to detect carrier and acquire sync (7 bytes of alternating 1’s and 0’s)

SFD - Start of Frame Delimiter

– Identifies the beginning of a frame (1 byte - 10101011)



Ethernet Media Access Control (MAC)

Ethernet Frame Fields

Addresses

– DA - Destination Address

– SA - Source Address

– Addresses have the following format - 00-80-C7-11-2D-29

– Each source address is unique

– First 3 bytes identify manufacturer, assigned by IEEE. Last 3 bytes are user value

Length/Type Field – use depends on frame type

– 802.3 frame - indicates length of data field (<=1500)

– Ethernet Type II (DIX) frame - indicates type of frame data (>=1536)



The Ethernet Frame

Data

– The payload

FCS - Frame Check Sequence

– A 32 bit cyclic redundancy check

performed on the frame for error

detection. Frames with CRC errors

are discarded at receiving station


Fields used for FCS calc


Frame Types

Unicast Frame

Frame which is destined to a single destination

Broadcast Frame

Frame which is destined to all the destination on the

network

Destination MAC Address:

FF-FF-FF-FF-FF-FF

Broadcast traffic can be very polluting because all the

stations on the network receive it and process it

Multicast Frame

Frame which is destined to a group of destinations

Destination MAC address:

01-00-5E-xx-xx-xx

More efficient than broadcast traffic

Pause Flow control frame is a multicast frame


Unicast

Unicast: Frames are sent

from one device to only one

other device.

The destination address

contains the MAC address

of the destination


Multicast

Multicast: Frames are sent

from one device to many

other devices which are

part of the multicast group

The destination address

contains a multicast group

address


Broadcast

Broadcast: Frames are

sent from one device to all

other devices in the

broadcast domain.

The destination address is

the Ethernet broadcast

address of

FF-FF-FF-FF-FF-FF


Ethernet layers 2 and 1 with IPG and IFS


SNAP, LLC, MAC

PMD = Physical Medium DependentPHY = Physical Layer ProtocolMAC = Media Access ControlLLC = Logical Link Control

OSI

Data

Link

Layer

OSI

Physical

Layer

Logical Link Control802.2

FDDI802.3

CSMA/CD

802.5TokenRing

802.11Wire-less

MAC

PHY

PMD

LLC

SNAPL2c

L2b

L2a Logical

Physical

IEEE 802.3

Ethernet v2

IEEE 802.3

Ethernet v2

LLC

SNAP


IPG and IFS

The Physical Layer rate 125 Mbps incase of 100M Ethernet Port and 1250Mbps incase of 1 GigE port.

IPG = Idle time between the transmission of 2 consecutive frames. IPG is at least 12bytes.

Minimum allowed IPG is 96 bit time:

– 96 nanoseconds at Gigabit Ethernet rate (1000BX)

– 0.96 microseconds at Fast Ethernet rate (100BT)

– 9.6 microseconds at Ethernet (10BT)

If frames are transmitted with minimum IPG the traffic is transmitted at maximum rate

IFS : InterFrame Spacing is at least 20 bytes which includes IPG, Preamble and SFD


Frame Rate

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)

– If max data rate is 1 Gbps (1000B-X) and data size is 64 bytes:

Frame rate = 1,488,095 Fps

– If max data rate is 100 Mbps (100B-T) and data size is 64 bytes:

Frame rate = 148,809 Fps

– If max data rate is 10 Mbps (10B-T) and data size is 64 bytes:

Frame rate = 14,880 Fps


Frame Rate and 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 %

If we take the example of Gigabit Ethernet we see

that efficiency increases with the frame length

It also applies to 10BaseT and 100BaseTX


Jumbo & Oversized Frames

Data field beyond 1518 bytes – up to 65535 bytes (vendor

dependent)

1518 bytes frame

98.7 % Efficiency

9018 data bytes

99.97% Efficiency

Why Jumbo then?

– Increase efficiency

– Decrease CPU time

FCS becomes less efficient for frames above 12000 bytes


Runts and Undersized Frames

RUNT: A frame that is greater than 2 bytes and less than

64 bytes, it has an SFD and a bad FCS (CRC error).

Generally fragments are caused by collisions, but may be

caused by faulty network equipment (e.g. network adapters,

hubs, etc.) Fragments are everyday occurrences on

moderately to heavily utilized networks.

Undersize frame: The frame which frame size is less than

64 bytes but there is no FCS Error.


VLAN – Virtual Local Area Netwok

Home of Acterna




VLANs

VLAN 1 VLAN 2

Broadcast

Domain

Broadcast

Domain


VLAN (Virtual Local Area Network)

Data (46-1500)L/T (2)SA (6)DA (6) FCS (4)SFD (1)Preamble (7) VLAN (4)

TPI Priority CFI VLAN ID

16-bits 3-bits 1-bit 12-bits

4 byte VLAN Specified in IEEE 802.1q/p

Developed to segment LANs and add traffic differentiation

Extends Ethernet frame size from 1518 to 1522 bytes

Contains 4 fields

– Tag Protocol Identifier – (fixed at hex 81-00 for Ethernet)

– Frame Priority Settings – (000 through 111)

– Canonical Frame Identifier – (used only in Token Ring)

– VLAN ID – (specifies the VLAN group ID)


Port Based Vlans

Vlan 1 Vlan 2 Vlan 3

Vlan 1 Vlan 2 Vlan 3


Tagged Based Vlans

Vlan

3

Vlan 1

Vlan 2

Vlan 3

Vlan

3

Vlan

2

Vlan

2Vlan

1

Vlan

1


VLANs

Switches can be part of multiple VlansVlans can transcend into different

switches in different locations


VLan, Access, and Trunk Links

Trunk

Access

No Vlan Option Required Use The Vlan Option


Why would a provider use VLAN?

Over-subscription for tiered service

Prioritize traffic – ensure low priority is dropped during periods of congestion

If bandwidth on Service B spikes to 800 Mbps, only 200 Mbps of Service A traffic will pass, the rest is discarded

1 Gigabit trunk

600 Mbps Service

Low Priority Traffic

800 Mbps Service

High Priority Traffic

Service A Service B

Ethernet Access Device

B=80%

A=20%


Traditional 802.1Q

Tagged Ethernet

FrameDestination

Address

Source

Address

Ether-

Type

FCSUpper-Layer

Protocol Data

802.1Q Tag

TPID CoS

Priority

VLAN

ID

C

F

I

Untagged Ethernet Frame

Destination

Address

Source

Address

Ether-

Type

FCSUpper-Layer

Protocol Data

Tag

Insertion


802.1Q Case Study

Dot1Q Trunk

Switch Switch

VLAN 10

VLAN 20

VLAN 10

VLAN 20

Physical

Logical

VLAN 10

VLAN 20


Anatomy of the 802.1Q Tag

The Q-Tag contains:– 16-bit Tag Protocol Identifier (TPID), EtherType 0x8100

– 3-bit Layer-2 Class-of-Service Priority Field (Values 0-7)

– 1-bit Canonical Format Identifier (CFI) — used for Token Ring & FDDI 802.1Q, normally set to zero

– 12-bit VLAN Identifier (Values 0-4095)

Ethernet Frame

Destination

Address

Source

Address

Ether-

Type

FCSUpper-Layer

Protocol Data

802.1Q Tag

TPID CoS

Priority

VLAN

ID

C

F

I


What if the Customer & Service Provider Use

802.1Q?

Service Provider

Network w/

802.1QPE

Switch

PE

Switch

CE

Switch

CE

Switch

Provider Perspective

CE

Switch

CE

Switch

Customer Perspective

Dot1Q Trunk


Q-in-Q Tunneling Mechanics (Ingress)

The Customer’s Frame with tag (C-Tag) is shifted and a Service Provider tag is inserted

The Service Provider uses the S-Tag to switch the frame. Various customer traffic is kept separate by the S-Tag

CE

Switch

PE

Switch

Untagged Ethernet Frame Tagged Ethernet Frame Q-in-Q Frame

802.1Q Tag 802.1Q Tag 802.1Q Tag

Service Provider

Network


Q-in-Q Tunneling Mechanics (Egress)

The Service Provider S-Tag removed before

switching the frame to the customer

Service Provider

Network

PE

Switch

CE

Switch

Untagged Ethernet FrameTagged Ethernet FrameQ-in-Q Frame

802.1Q Tag802.1Q Tag 802.1Q Tag


Anatomy of Q-in-Q

The TPID identifies the frame as 802.1Q. The S-Tag TPID is vendor proprietary.

Some vendors use a unique TPID for the S-Tag to identify the frame as Q-in-Q.

The C-Tag TPID is always 0x8100. Some common S-Tag TPID values:

– 0x9100

– 0x9200

– 0x88a8

The Canonical Format Identifier (CFI) has been redefined to be used for Discard

Eligible (DE), similar to Frame Relay DE.

– Set when customer bursts over their Committed Info Rate (CIR)

– Network discards frames with DE set when congestion is experienced

Ethernet

Frame

D

A

Ether-

TypeFCSData

802.1Q Customer Tag

(C-Tag)

TPID CoS

Priority

VLAN

ID

C

F

I

S

A

802.1Q Service Provider Tag

(S-Tag)

TPID CoS

Priority

VLAN

IDD

E


Enterprise VLAN

VLAN 200

VLAN 100

VLAN 100

VLAN 100

VLAN 200

VLAN 200TRUNK Voice VLAN 200

Data VLAN 100

VLAN 200

VLAN 100

VLAN 200

TRUNK Voice VLAN 200

Data VLAN 100

VLAN 100

VLAN 200

TRUNK

Voice VLAN 200Data VLAN 100

VLAN 100


Metro Ethernet and Vlans

Trunk Link Trunk Link


Enterprise / Metro Ethernet ? And VLANs

VLAN 200

VLAN 100

VLAN 100

VLAN 100

VLAN 200

VLAN 200TRUNK VLAN 200

VLAN 100

VLAN 200

VLAN 100

VLAN 200

TRUNK VLAN 200

VLAN 100

VLAN 100

VLAN 200

TRUNK

VLAN 200VLAN 100

VLAN 100


Testing with Vlans

1

2

3

2

Tagged Ports

Non Tagged PortsTRUNK


Provider Environment VLANS - 802.1Q in 802.1Q ( VLAN

Stacking)

Preamble SFD Destination

MAC Address

Source

MAC Address

Length /

Type

Etype

and

802.1Q

TAG

Etype

and

802.1Q

TAG

Data FCS


MAC Address

Source

MAC Address

Length /

TypeEtype

and

802.1Q

TAG

Data FCS


MAC Address

Source

MAC Address

Length /

Type

Data FCS

Standard Ethernet Frame

Ethernet Frame with Vlan Tag

Ethernet Frame with 802.1Q in 802.1Q Provider Tag


Priority and Priority Queues

Manufactures have different defaults

Defaults can be changed

A high priority on one device might be a lower priority on another device

It is recommended to use prioritization instead of flow control to control the flow of traffic

1 0-1

2 2-3

3 4-5

4 6-7

1 0-2

2 3-4

3 5-6

4 7

Queues Priority PriorityQueues

Switch Brand A Switch Brand B


Class of Service (CoS)

CoS 5

CoS 2 CoS 2

CoS 5

CoS 3CoS 3


Ethernet Vs. SDH

Home of Acterna




SDH/Ethernet Comparison

Layer 1 - SDH Ethernet L1 & L2

Application

Presentation

Session

Transport

Network

Datalink

Physical

Application

Presentation

Session

Transport

Network

Physical

OSI Layer Model

Datalink

IP

ATM

SDH Ethernet

IP

Ethernet



SDH Ethernet

OC-12

RING

Designed for voice

traffic

– Synchronous

Designed for data

traffic

– Asynchronous



Designed for voice

traffic

– Fixed frame size

Designed for data

traffic

– Variable Frame size

SDH

Ethernet

SDH Ethernet



Designed for voice

traffic

– Constant bit rate

Designed for data

traffic

– Bursty traffic

SDH Ethernet

SDH

Ethernet

Bit

Rate

time


Ethernet Services

Home of Acterna




Metro Ethernet

3550

Core

7609

Edge EdgeAccess Access

Customer

Device 7609 7609

76097609

7609

Demarcation

Point

Demarcation

Point

Customer

Device

•Switched based Architecture

•Uses VLAN for the switching in the network

•Major Players

• Cisco – 6509/7609/15454

• Nortel - 8600

Service ProviderEnd User End User

3550

LAN


L1 Metro Ethernet Services

Providers Switch

Customer Ethernet

SwitchesSONET / SDH Ring

• Provider Switches configured to map between Switches and Ports

• Transparent Frame in Frame out service with no MAC awareness

Providers Switch

Providers Switch

•Customer switches learns addresses


L2 Metro Ethernet Services

Providers Switch

Customer Ethernet

SwitchesSONET / SDH Ring

• Provider Switches ―auto-learn‖ every local MAC Address

• Provider Switches exchange MAC location information

• Each packet directed to appropriate destination Switch / port

Providers Switch

Providers Switch

• Bandwidth available at less than 1Gig or 100Meg rates


Common Ethernet Offerings

Single 1G pipes (DWDM)

Multiple 1G pipes (DWDM)

Multiple 1G pipes (CWDM)

Ethernet over SDH

Virtual Private Line Ethernet

Fibre Channel (1G and 2G)

10G Ethernet


Private Line Service (1G) (CWDM)

Point to Point

1 GigE pipe only

Physical Layer Only – No frame aware devices in circuit path (L1)

Point to Point Optical Network

Location A

Central Office

Location B


Testing Private Line Service (1G) (CWDM)

Generate Traffic at customer premise

Loopback at CO can be done by 2802 or hard loop

FST-2802

FST-2802

Point to Point Optical Network

Location A

Central Office

Location B


Point to Point

Multiple GigE pipes in one location (2-4)

Physical Layer only (L1)

Handoff

CWDM Optical Network

Location B

Location A

Central Office

Private Line Service (2G+) (CWDM)



Location B

Location A

Central Office

Private Line Service (2G+) (CWDM)

Hard Loop

or

Generate traffic between customer premises or to central

office

Loopback at CO can be done by 2802 or hard loop

Multiple 1Gig pipes must be tested at multiple locations


Ethernet over SDH (Private Line)

-Fractional 1G Transport Service

Getting more complex

– point to point or switched

– 10/100 and Gigabit interfaces

– Not always a full Gigabit

• configurable bandwidth in STS increments

– Flow control may be enabled

SDH Ring

OC-48 or OC-192

Customer GigE Switch

Ethernet

Link A

Ethernet

Link B

SDH Link

Cisco 15454


Testing Ethernet over SDH

Hard loop generally no longer certainty

– Depends on network element (L1 or L2)

2802 generates traffic at customer premise, 2802 in location B loops traffic back

2310/2510A is used to troubleshoot SDH ring

SDH Ring

OC-48 or OC-192

Ethernet

Link A

Ethernet

Link B

SDH Link

Loopback Mode


Virtual Private Line Ethernet

Most Complex

– Switched service (L2 device)

– VLANs are utilized

– 10Mb, 50Mb, 100Mb, 200Mb, 500Mb, or 1000Mb links

– Link Partner is near end NE instead of far end test set

Core

35503550

7609

Edge EdgeAccess Access

CPE CPE7609 7609

76097609

7609

Demarcation

Point

Demarcation

Point

10/100

Ethernet10/100

EthernetGigabit

EthernetGigabit

Ethernet

MPLS


Single Ended Turn-Up

Single tech is dispatched to customer site

Test is controlled through the Test Center

Test Center sends traffic

Traffic is returned via loop back at customer site or tested head-to-head

35503550

Core

7609

Edge EdgeAccess AccessCustomer

Device

7609 7609

76097609

7609

Demarcation

Point

Demarcation

Point

Testing

Centeror

GigE

Loopback Mode


Fibre Channel (uncommon)

Transmits Fibre Channel over CWDM circuit

Used for Storage Area Networks

True QoS guarantee

Same as Private Line Ethernet, just different protocol

Handoff


Location B

Location A

Central Office


10G Ethernet (future)

10 GigE using Optical Transport

Used both as Transport and for Customer Sites

Test similar to 1G Ethernet

Handoff

Alcatel/Cisco

10GigE Optical Network

Location B

Location A

Central Office


Ethernet Testing Methodologies

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Testing Methods

Out of Service Test

– Layer 1 Loopback

– Layer 2 Loopback

– End to End Testing

– Round Trip Delay

In-Service Test

- Bidirectional Monitoring

- Monitoring in Through Mode

- Monitoring with Splitter / Tap port

- Monitoring on Mirrored port


Loopback testing:

Hard-wire Loopback (Layer 1)

(non-switched networks)

TX

RX

LOS

ACTIVE

STATUS

FST-2802

Near-endAccess Element/

Ethernet Device

TX

RX

LOS

ACTIVE

STATUS

Far-endAccess Element/

Ethernet Device

Layer 1 Loopback

Out of service testing


Specify the far-end Test Pad's source address as the

destination address for the first TestPad and vice versa

Source address for the TestPad can be

found under the Summary tab

End to End testing



End-to-end testing

Select Traffic and specify the traffic load type

If 1G Ethernet: select Laser Off to turn laser on

Select Start Traffic on both TestPads

View and verify results

End to End testing




TX

RX

LOS

ACTIVE

STATUS

FST-2802

(Data Source)

Near-end

TX

RX

LOS

ACTIVE

STATUS

FST-2802

(Unit reverses source and

destination MAC addresses)

Far-end

(Switched networks)

Manual Loopback:

Far-end

device:

Loopback Testing


Automatic Loopback:

On transmitting TestPad

select Loop Up to put

receiving TestPad in

loopback mode

Select Start Traffic

Verify results

When test is complete,

select Loop Down

(Switched networks)


Loopback Testing


Setup and configure a

Loopback test

Define a profile with an

Acterna payload

If 1G, turn laser on

Start traffic

Verify on Results Panes

the following Link Stats:

– Delay, Max (s)

– Delay, Min (s)

– Delay, Avg (s)

TIMESTAMP TIMESTAMP TIMESTAMP

TIMESTAMP TIMESTAMP TIMESTAMP

23 1

21 3


Round Trip Delay


Sit on a link and monitor traffic in both directions

Filter on customer traffic or watch link for errors

Requires a dual port 2802

Testing – Bi-directional Monitoring


Test Access Points- In-line

WAN

FST-2802

Provider Edge

FST-2802

PE

PE

PE

Customer Edge

Through mode-

In-line

Through mode-

In-line

CE

CE

CE


Test Access Points- Splitter- Optical Tap


Test Access Points- Mirrored Port

MirrorED PortsMirror Port


Q & A

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ethernet technology training

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measurement

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