IEEE 802.3Z Gigabit Ethernet ANSI X3T9 Fibre Channel Ethernet

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IEEE 802.3 Ethernet IEEE 802.3u Fast Ethernet IEEE 802.3z Gigabit Ethernet ANSI X3T9 Fibre Channel Ethernet – Table of Contents

Part 1: IEEE 802.3 Ethernet

Part 2: IEEE 802.3u Fast Ethernet Floor 4

Ethernet / Fast Ethernet Switch Part 3: IEEE 802.3z Gigabit Ethernet Floor 3

Hub Stack

Bridge / Router Fast WAN Ethernet Switch Floor 1

Broadband Network Technologies IEEE 802.3 Ethernet 2 Ethernet – History

• Developed by Xerox Palo Alto Research Centre

• First published by Digital Equipment, Intel, and Xerox as DIX (DEC, Intel, Xerox) standard

• Strongly changed and standardised by IEEE in the IEEE 802.3

• Therefore, two different versions are existing: – Ethernet version 2 (DIX) – IEEE 802.3 – differences are mainly in the Media Access frame

• Topology of an Ethernet is logically (mostly physically, too) a bus

Broadband Network Technologies IEEE 802.3 Ethernet 3 Ethernet – Technological Overview

• A lot of standards exist for different Ethernet versions: – 1Base5 (Starlan), 10Base5 (Ethernet), 10Base2 (Cheapernet) – 10BaseT, 10BaseF, 10Broad36 – 100BaseTX, 100BaseFX, 100BaseT2, 100BaseT4 – 1000Base-LX, 1000Base-SX, 1000Base-CX, 1000Base-T – 100BaseVG, 100VG-AnyLAN

• First number identifies transfer rate (1=1MBit/s, 10=10MBit/s, ...)

• Base = baseband transmission, Broad = broadband transmission

• Last digit, number, or character identifies characteristics of the transmission medium: – T = twisted pair, FX/LX/SX = fibre optics, CX = shielded balanced copper, T4 = 4 pair twisted pair, T2 = 2 pair twisted pair – length of a segment - 2=185m, 5=500m

Broadband Network Technologies IEEE 802.3 Ethernet 4 Part 1: Survey

Part 1: IEEE 802.3 Ethernet – Physical Layer – Medium Access – Configuration Rules

Part 2: IEEE 802.3u Fast Ethernet

thick coax Part 3: IEEE 802.3z Gigabit Ethernet segment (500m max) coax MAU tap (MDI)

15-pin AUI connector transceiver AUI cable (50m max)

Ethernet interface male "N" connector with external MAU 50 Ohm terminator

Broadband Network Technologies IEEE 802.3 Ethernet 5 IEEE 802.3 Ethernet – Introduction

Applications

Management

CSMA/CD MAC

AUI Interface

10Base5 10Base2 10Base-T 10Base-F (Thick Coax) (Thin Coax) (UTP cat 3,4,5) (Fibre)

Ethernet Physical Layer (PHY) Options

Broadband Network Technologies IEEE 802.3 Ethernet 6 Physical Layer

• Tasks of the physical layer defined as:

– send and receive bit streams

– collision detection

– encoding and decoding of signals

– generation of the preamble

– generation of clocks for synchronisation

– testing of the transmission of data from the station up to the Medium Access Unit (MAU)

Broadband Network Technologies IEEE 802.3 Ethernet 7 Physical Layer (cont.) – Architectural Model

Higher Protocol Layer

Logical Link Control (LLC)

Medium Access Control (MAC)

PLS

standardised in IEEE 802.3 AUI

Physical Layer Physical PMA

MDI MAU

transmission medium

PLS Physical Signalling Sub-layer MDI Medium Dependent Interface AUI Attachment Unit Interface MAU Medium Attachment Interface PMA Physical Medium Attachment

Broadband Network Technologies IEEE 802.3 Ethernet 8 Medium Access – CSMA/CD

• Shared medium access is realised with Carrier Sense Multiple Access with Collision Detection (CSMA/CD) – each station is listening to the carrier (carrier sense) – if no transmission takes place, stations can send data to any other station (multiple access) – if two or more stations send data at the same time, each station has to stop further transmission (collision detection) – after a certain time (random for each station), stations can try to send data again

• CSMA/CD needs – multiple stations connected to a segment (multiple access) – sense of the carrier before data is sent (carrier sense) – sense of the carrier during data transmission (collision detection)

Broadband Network Technologies IEEE 802.3 Ethernet 9 Medium Access (cont.) – Domains

Bridge / Repeater / Router Switch Hub

Ethernet Ethernet Ethernet Ethernet

Collision Domain

Broadcast Domain

Broadband Network Technologies IEEE 802.3 Ethernet 1 Medium Access (cont.) – IEEE 802.3 Frames

IEEE 802.3 Ethernet MAC frames

PA SFD DA SA LEN LLC Data PAD FCS 7 1 646 2 3/4 variable

PA preamble LLC logical link control DA destination address PAD padding SA source address FCS frame check sequence (CRC-32) SFD start frame delimiter LEN length

Broadband Network Technologies IEEE 802.3 Ethernet 1 Configuration Rules

• Basically two models exist for the configuration of multi-segment Ethernet networks:

1. A model employing conservative calculations

2. A model employing IEEE standardised configuration aids with two phase calculation (first the correct round trip signal propagation, than the amount of Interframe Gap shrinkage)

• System not built with these guidelines can work, but usually not for a long time

• Especially a growing network (by size or traffic load) should not violate this recommendations (IEEE 802.3)

Broadband Network Technologies IEEE 802.3 Ethernet 1 Configuration Rules (cont.) – Model 1

10Base-FL link 500m R 500m R 10Base-5 mixing 10Base-FL link 500m 500m DTE 2 10Base-5 mixing 10Base-T link DTE 3 R 100m R DTE 1 185m 10Base-2 mixing

R Repeater

Broadband Network Technologies IEEE 802.3 Ethernet 1 Configuration Rules (cont.) – Model 2

• Defines two sets of methods, which have to be performed both

• First set ensures that the round trip signal propagation is within the limits

• Second set verifies the amount of Interframe Gap shrinkage

• A simplified network topology (Generalised Transmission Path Model) is used to for the path delay calculation

DTE DTE MAU MAU Repeater MAU MAU Repeater MAU MAU 1 2

left segment middle segment right segment

Broadband Network Technologies IEEE 802.3 Ethernet 1 Part 2: IEEE 802.3u Fast Ethernet

Part 1: IEEE 802.3 Ethernet

Part 2: IEEE 802.3u Fast Ethernet – Introduction – 100Base-T Overview – 100Base-TX – 100Base-FX – 100Base-T4

Ethernet / Fast Ethernet / Fast Ethernet Switch Ethernet Switch Part 3: IEEE 802.3z Gigabit Ethernet

Fast Ethernet Hub

Broadband Network Technologies IEEE 802.3 Ethernet 1 Fast Ethernet – Technological Overview I

• Two different technologies exist for 100MBit/s Ethernet – IEEE 802.3u 100Base-T (100Base-TX, 100Base-FX, 100Base-T4, 100Base-T2) – IEEE 802.12 100VG-AnyLAN

• 100Base-T – supports the common Ethernet mechanisms (CSMA/CD)

• 100VG-AnyLAN – creates an entirely new medium access control mechanism – is based on hubs that control access to the medium using a demand priority – further extended to allow to transport token ring frames

Broadband Network Technologies IEEE 802.3 Ethernet 1 Fast Ethernet – Technological Overview II

100 MBit/s Ethernet

100VG-AnyLAN 100Base-T

100Base-T2 100Base-X 100Base-4

100Base-TX 100Base-FX

Broadband Network Technologies IEEE 802.3 Ethernet 1 IEEE 802.u Fast Ethernet

• Aims of the IEEE 802.3u Fast Ethernet working group – support of CSMA/CD with bit rate of 100 MBit/s – identical MAC frame format – support of twisted pair and fibre optics as physical medium – interoperability between 10Base-T and 100Base-TX components

• Fast Ethernet Consortium develops technology and is accepted by the IEEE 802.3u working group

• The Fast Ethernet Consortium was formed in December of 1993 and is one of the consortiums at the University of New Hampshire Inter Operability Lab (IOL). The Consortium was formed through the co- operative agreement of vendors interested in testing Fast Ethernet products.

Broadband Network Technologies IEEE 802.3 Ethernet 1 IEEE 802.u Fast Ethernet (cont.) – Overview

Applications

Management

CSMA/CD MAC

MII Interface

100Base-FX 100Base-TX 100Base-T4 (Fibre) (UTP cat 5) (UTP cat 3,4,5)

Fast Ethernet Physical Layer (PHY) Options

Broadband Network Technologies IEEE 802.3 Ethernet 1 Physical Layer – 100Base-X

Scheme of the 100Base-X standard

LLC

MAC

Reconciliation

MII 100Base-X repeater

PCS PCS PCS Physical PMA PMA Layer PMA

PMD PMD PMD

MDI MDI MDI

Medium Medium

Broadband Network Technologies IEEE 802.3 Ethernet 2 Physical Layer (cont.) – 100Base-T4

Scheme of the 100Base-T4 standard

LLC

MAC

Reconciliation

MII

PCS

PMD

MDI

Medium

Broadband Network Technologies IEEE 802.3 Ethernet 2 Physical Layer (cont.) – 10/100 MBit Hub

Scheme of a Fast Ethernet hub supporting different media

10Base-T / 100Base-TX repeater

Reconciliation Reconciliation PLS

MII MII

PCS PCS Physical Layer PMA AUI AUI

PMD PMA PMA (= MAU)

MDI MDI MDI

Medium Medium Medium 100 MBit/s 10 MBit/s 10 MBit/s

Broadband Network Technologies IEEE 802.3 Ethernet 2 Media System

• 100Base-T is ten times faster than 10Base-T • Common 10Base-T aspects are unchanged – frame format and the amount of data of a frame – media access control • Mechanisms for Auto-Negotiation of media speed added – enables support of dual-speed Ethernet interfaces (10 and 100 MBit/s) • Block diagram of 100Base-T components:

Data Terminal Physical Medium Equipment Medium Independent Physical Layer Dependent (DTE) Interface (MII) Medium Device (PHY) Interface (MDI) port

40-pin connector optional

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-TX – Components I

class II four port 100Base-TX repeater hub

R II PHY PHY PHY PHY eight pin plugs

twisted pair segment (100m max of data graded UTP cat 5 cable) PHY

eight pin jack MDI Ethernet interface (100Base-TX)

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-TX (cont.) – Components II

• 100Base-TX segments are link segments • A link segment is defined as a point-to-point medium – connects two and only two MDIs – smallest network would consist of two computers

• Typical installation uses multiport repeater hubs or packet switching hubs – provides a connection between a larger number of link segments – NIC on one end, hub on the other end of the segment – hubs can connect as many segments as ports available – computers all communicate via the hub

• Segment up to 100m • Two 100m segments segments can be connected through a single Class I or Class II repeater • System with a total diameter of 200 meters between DTEs

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-T (cont.) – Repeater I

Data Circuit Equipment (repeater, hub)

• Ethernet ports on repeaters do not use an Ethernet interface – A repeater port connects to the Fast Ethernet media system with the same PHY and MDI equipment – moving the signals directly from segment to segment, therefore, do not contain Ethernet interfaces (since they do not operate at the level of Ethernet frames) – a repeater hub may be equipped with an Ethernet interface to provide a way to communicate with the hub over the network (allows a vendor to provide a management interface in the hub)

• Two kinds of repeaters in the 100Base-T system (labelled with the Roman number "I" or "II" centred within a circle) – Class I – Class II

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-T (cont.) – Repeater II

Class I repeater have larger timing delays – operates by translating line signals on an incoming port to digital form – then retranslating them to line signals when sending them out on the other ports – repeats signals between media segments that use different signalling techniques (e.g. 100Base-TX/FX and 100Base-T4 segments) – only one Class I repeater can be used in a given collision domain when maximum cable lengths are used

• Class II repeater is restricted to smaller timing delays – immediately repeats the incoming signal to all other ports – connected only to segment types that use the same signalling technique a maximum of two Class II repeaters can be used within a given collision domain when maximum cable lengths are used • Segment types with different signalling techniques cannot be mixed together in a Class II repeater hub

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-TX (cont.) – Link Integrity Test

• PHY continually monitors the receive data path for activity – checks that the link is working correctly (also in idle periods) – signalling system is based on the ANSI FDDI signalling

• Twisted-pair transceivers that use 8-pin MDI connectors also send and receive link pulses – called Fast Link Pulses (FLP) – used in the Auto-Negotiation mechanism – allows a multi-speed hub to detect the speed of operation of an Ethernet device – hub can adjust the speed of its ports accordingly

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-FX – Components

class II 100Base-FX fibre optic repeater hub

R II

TXRX TXRX TXRX

FO link to another TX FO station or RX repeater hub

Ethernet interface SC, ST, or (100Base-FX) FDDI fibre optic connector

Broadband Network Technologies IEEE 802.3 Ethernet 2 100Base-T4 – Components

class II four port 100Base-T4 repeater hub

R II PHY PHY PHY PHY eight pin plugs

twisted pair segment (100m max of four pair UTP cat 3,4,5 cable) PHY

eight pin jack MDI Ethernet interface (100Base-T4)

Broadband Network Technologies IEEE 802.3 Ethernet 3 100Base-T4 - Components

• Old „voice-grade“ twisted pair (Cat3) has high attenuation and electromagnetic radiation • UTP Cat3 is only defined up to 16 Mbit/s • Radiation is limited by the authorities above 30 MHz

• Therefore 4 pairs working in parallel at 25 Mbit/s • Special attention ís paid to signal encoding

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration – From Ethernet to Fast Ethernet

• Fast Ethernet is compatible with Ethernet – shared medium, too – CSMA/CD is the same – old cabling can be used, if UTP cat 5 – 10Base-T network cards can be connected to 100Base-T equipment

• Differences – new network cards needed (dual cards available) – coax cable no longer supported – integration can be accomplished with switches rather then routers – maximum hop count between stations (repeater, hub) is 2 (Ethernet: 4), larger networks have to employ bridges, switches, or routers – maximum network diameter between two stations in the same segment is 205 m (twisted pair)

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – Cable Pinout

• 100Base-TX Cable Pinout Desktop Hub 1 1 2 Transmit (1&2) 2 3 3 4 Receive (3&6) 4 5 5 6 6 7 7 8 8

• 100 Base-T4 Cable Pinout Desktop Hub 1 1 2 Transmit (1&2) 2 3 3 4 4 5 Receive (3&6) 5 6 6 7 Bi-directional (4&5) 7 8 8 Bi-directional (7&8)

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – Switched vs. Fast Ethernet

Fast Ethernet Switched Ethernet

Seldom makes sense to the desktop; Obvious upgrade path: use for servers only: • Low cost; no adapter change Existing • Most existing PCs cannot take • Workgroups Leverages existing PCs advantage of 100 MBit/s • No cable change • Costs of changing adapters • Multimedia capable

For power users and peak bandwidth Or standard business applications needs and aggregate bandwidth needs • 100MBit/s peak bandwidth for • Lower costs CAD/CAM, graphics, 3D Modelling, • Standard Ethernet cabling New etc. • Workgroups Ideal for ISA, PC-Card (PCMCIA) • Only slightly higher costs than PCs switched 10MBit/S • Ideal for PCs and PCI PCs and UNIX workstations

Peak performance – new Continuous network use – ISA PCs Summary PCs/workstations with large file transfers and installed base

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – Small Fast Ethernet Collapsed Backbone

Ethernet Hub

shared 10MBit/s switched 10MBit/s

switched 100MBit/s Ethernet Hub shared 100 MBit/s

Ethernet / Fast Ethernet Switch Fast Ethernet Hub

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – Switched Ethernet with Fast Ethernet

Ethernet / Fast Ethernet / Fast Ethernet Switch Ethernet Switch

switched 10MBit/s

switched 100MBit/s

shared 100 MBit/s Fast Ethernet Hub

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – High Performance Workgroups

Floor 4

Ethernet / Fast Ethernet Switch

Floor 3

Hub Stack switched 10MBit/s

switched 100MBit/s

shared 100 MBit/s Floor 2

Hub Stack

FDDI

Bridge / Router Fast Ethernet Switch Floor 1 WAN

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – Comprehensive Fast Ethernet Integration

Floor 4

Ethernet / Fast Ethernet Switch

Floor 3

shared 10MBit/s Ethernet Hub switched 10MBit/s

switched 100MBit/s

shared 100 MBit/s Floor 2

Fast Ethernet Switch

LAN Switch Bridge / Router Fast FDDI WAN Ethernet Switch Floor 1

Broadband Network Technologies IEEE 802.3 Ethernet 3 Migration (cont.) – Scale Fast Ethernet and an FDDI Backbone

Floor 2 Floor 2

Hub with 100 MBit/s Hub with 100 MBit/s downlink downlink

Floor 1 Floor 1

Hub Stack Hub Stack

Fast Fast Ethernet Switch Ethernet Switch

LAN Switch with support for bridging, FDDI FDDI concentration, Bridge / Router and IP routing backbone switched 10MBit/s

switched 100MBit/s

shared 100 MBit/s

Broadband Network Technologies IEEE 802.3 Ethernet 3 Topology Rules

• Maximum Network Diameter Repeater Qty. Twisted Pair Fibre Twisted Pair /Fibre Class TX/T4 100Base-FX TX/FX T4/FX I 1 200 m 272 m 260.8 m 231 m 656 ft. 892.2 ft. 855.4 ft. 57.7 ft. II 1 200 m 320 m 308.8 m 304 m 656 ft. 1,049.6 ft. 1,012.9 ft. 997.1 ft. II 2 205 m 228 m 216.2 m 236.3 m 672.4 ft. 747.8 ft. 709.1 ft. 775.1 ft.

• Maximum Cable Distances Cable Type Connecting Length 100m Twisted Pair Any two devices 328 ft. Half 142 m Switch to Switch, Duplex 1,351.4 ft. Fibre Server or PC Full 2 km Duplex 1.24 mi.

Broadband Network Technologies IEEE 802.3 Ethernet 4 Topology Rules (cont.)

MAC - MAC Floor 100 412m fibre

100Base-T Switch or Bridge

one repeater: 261m Floor 50 (161m fibre + 100m UTP)

100Base-T Class I hub 100m UTP

two repeaters: 205m Floor 25 (typically 100m + 5m + 100m)

100m UTP 100m UTP

100Base-T 100Base-T Class II hub Class II hub 5m UTP

switched 100MBit/s Bridge / Router Switch shared 100 MBit/s

Broadband Network Technologies IEEE 802.3 Ethernet 4 Part 3: IEEE 802.3z Gigabit Ethernet

Part 1: IEEE 802.3 Ethernet

Part 2: IEEE 802.3u Fast Ethernet

Part 3: IEEE 802.3z Gigabit Ethernet T T HYBRID HYBRID – The need for speed – Functional Elements R R T T – Architectural Model HYBRID HYBRID

– 1000Base-T R R

T T –Migration HYBRID HYBRID

R R

T T HYBRID HYBRID

R R

Broadband Network Technologies IEEE 802.3 Ethernet 4 Gigabit Ethernet – The Need for Speed

Not-compressed Compressed Jitter Audio (CD quality) 1.4 MBit/s 192 kBit/s 100 ms

Speech 64 kBit/s 4 – 32 kBit/s 400 ms

Video – HDTV 2 GBit/s 25 – 34 MBit/s 50 ms (MPEG-2) Video – studio quality 166 MBit/s 3 – 6 MBit/s 100 ms (MPEG-2) Video – TV quality – 2 – 4 MBit/s 100 ms (MPEG-2) Video – video conference – 112 kBit/s 400 ms quality (H.261)

Broadband Network Technologies IEEE 802.3 Ethernet 4 IEEE 802.3z Gigabit Ethernet – Protocol Stack

IEEE 802.2 LLC

IEEE 802.3 IEEE 802.3 Ethernet CSMA/CD IEEE 802.3 IEEE 802.2 LLC Physical Layer CSMA/CD or Full Duplex MAC

8B/10B FC-4 Upper Layer Encode/Decode Mapping FC-3 Common Serializer/ Services Deserializer ANSI X3T11 FC-2 Signalling Fibre Channel Connector FC-1 Encode/Decode FC-0 Interface and Media

Broadband Network Technologies IEEE 802.3 Ethernet 4 Standardisation Timeline

1995 1996

HSSG PAR PAR 802.3z Formed Drafted Approved Approved

1997 1998

LMSC First Draft Working Standard Group Ballot Ballot

HSSG Higher Speed Study Group PAR Project Authorisation Request LSMC LAN MAN Standards Committee

Broadband Network Technologies IEEE 802.3 Ethernet 4 IEEE 802.3z Gigabit Ethernet – Overview

Applications

Management

CSMA/CD MAC

GMII Interface

1000Base-CX 1000Base-SX 1000Base-LX 1000Base-T (Twinax) (Short WL Fibre) (Long LW Fibre) (Twisted Pair)

Gigabit Ethernet Physical Layer (PHY) Options

Broadband Network Technologies IEEE 802.3 Ethernet 4 IEEE 802.3z Gigabit Ethernet – Overview (cont.)

• GbE is still Ethernet, only faster

• New functional capabilities: – Full-duplex operation • Allows simultaneous two-way transmission • The possibility of collisions is eliminated and the effective bandwidth is doubled – Flow Control • Optional flow control allows to avoid receiver buffer overflows – VLAN Tagging • Allows the creation of virtual networks based on logical identification rather than physical addresses • Reduces the number of addresses that must be maintained in switch tabels • Allows to assign user priorities within an Ethernet • Requires to change the frame format (if used, we are no longer compatible to the other Ethernets)

Broadband Network Technologies IEEE 802.3 Ethernet 4 IEEE 802.3z Gigabit Ethernet – Functional Elements

Media Access Control (MAC) full duplex and/or half duplex

Gigabit Media Independent Interface (GMII), optional

8B / 10 B 1000Base-T encoding / decoding encoder / decoder

1000Base-LX 1000Base-SX 1000Base-CX 1000Base-T LWL SWL Shielded Balance UTP Fibre Optic Fibre Optic Copper Category 5

SMF - 5 km 50µ MMF - 550 m 25 m 100 m 50µ MMF - 550 m 62,5µ MMF - 275 m 62,5µ MMF - 550 m 802.3ab 802.3z physical layer physical layer

Broadband Network Technologies IEEE 802.3 Ethernet 4 IEEE 802.3z Gigabit Ethernet – Distance Specifications

9µ MMF 1000Base-LX 50µ MMF 1300nm 62.5µ MMF

1000Base-SX 50µ MMF 850nm 62.5µ MMF

1000Base-T Copper(UTP) 1000Base-CX Copper(twinax)

25m 100m 275m >500m 5km Machine Room Building Backbone Campus Backbone

Broadband Network Technologies IEEE 802.3 Ethernet 4 IEEE 802.3z Gigabit Ethernet – Architectural Model

Upper Layers

Logical Link Control (LLC) Data Link Layer Media Access Control (MAC)

Reconciliation Reconciliation

MII GMII

PCS PCS Physical Layer PMA PMA PMD PMD

MDI MDI

Medium Medium 100 MBit/s 1000 MBit/s

Broadband Network Technologies IEEE 802.3 Ethernet 5 IEEE 802.3z Gigabit Ethernet – Frame Transmission

• Half-Duplex mode: • Basically like classical Ethernet (Carrier sense, collision detection) • But: the data frame is much shorter now! • Two possible solutions: • Increase the minimum frame length or • Add non-data carrier-extension bits after the frame transmission • The latter does not violate the standard, so it was chosen 7 1 646 2 3/4 variable PA SFD DA SA LEN LLC Data PAD FCS Extension minFrameSize slotTime Late collision threshold (slot time) Carrier duration PA preamble LLC logical link control DA destination address PAD padding SA source address FCS frame check sequence (CRC-32) SFD start frame delimiter LEN length

Broadband Network Technologies IEEE 802.3 Ethernet 5 IEEE 802.3z Gigabit Ethernet – Frame Transmission

• Another possibility to extend the carrier is Frame bursting – Allow a user to send a series of (small) packets without relinquishing the control of the medium

MAC frame w. extension Interframe MAC frame Interframe MAC frame Burst limit Carrier duration

– When the burst limit is reached, the last frame may be continued without interruption

Broadband Network Technologies IEEE 802.3 Ethernet 5 1000Base-T – The Challenge

• Transmitting 1000 MBit/s data stream over four pairs of UTP cat 5 cable presents several design challenges due to: – signal attenuation – echo – return loss – crosstalk characteristics • NEXT - Near-end Crosstalk • FEXT - Far-end Crosstalk • ELFEXT - Equal Level Far-end Crosstalk • Transmission systems operating on UTP cable must be capable of withstanding radiated energy from other sources (AM, CD, short wave radio) • Additional objective is to maximise the tolerance to background and impulse noise (power line transients, electrical fast transients, Electro- static discharge - ESD)

Broadband Network Technologies IEEE 802.3 Ethernet 5 1000Base-T (cont.) – The Design Approach

T Insertion_Loss (f) T HYBRID HYBRID

250 MBit/s echo Pair 1 250 MBit/s

R R

T NEXT_21 FEXT_21 T HYBRID HYBRID

250 MBit/s Pair 2 250 MBit/s

R R

T NEXT_31 FEXT_31 T HYBRID HYBRID

250 MBit/s Pair 3 250 MBit/s

R R FEXT_41 T NEXT_41 T HYBRID HYBRID

250 MBit/s Pair 4 250 MBit/s

R R

Broadband Network Technologies IEEE 802.3 Ethernet 5 1000Base-T (cont.) – Transceiver

TX Magnetics

Pulse Resistive DAC Shaping Hybrid Auto Negotiation PCS Transmit GMII Synch A/D

Tuning PLL Control

NC NC NC NC

Delay Adj. Σ FFE

Viterbi PCS Decoder/ Receive DFE

Broadband Network Technologies IEEE 802.3 Ethernet 5 1000Base-T (cont.) – 5-level PAM Coding

1 Binary signalling

0 Baseband Pulse Symbol Shaping GMII +2 Encoder +1 0 -1 125 MHz 125 MHz, 5 levels

-2 1000Base-T 5-level PAM

• Four symbols transmitted simulataneously on the four pairs make up an 8-bit octet (4D-PAM5 Trellis FEC code) • One octet is transmitted in only one baud, making up 125 Mbaud per twisted pair

Broadband Network Technologies IEEE 802.3 Ethernet 5 Migration – Switch to Server Links

End User Connection 100 MBit/s 100 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s

100 M 100 M 10 M 10 M 10 M 10 M Repeater Repeater Switch Switch Switch Switch

100 100 100 100 100 100

MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s

i B

Fast Ethernet Switch M

0 1

Server Farm

End User Connection 100 MBit/s 100 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s

100 M 100 M 10 M 10 M 10 M 10 M Gigabit Repeater Repeater Switch Switch Switch Switch Ethernet NICs

100 100 100 100 100 100

MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s

i B

Gigabit Ethernet Switch or Repeater M 0

0 1 Server Farm

Broadband Network Technologies IEEE 802.3 Ethernet 5 Migration (cont.) – Switch to Switch Links

End User Connection End User Connection

10 MBit/s 10 MBit/s 100 MBit/s 100 MBit/s 10 MBit/s 10 MBit/s

10 M 10 M 100 M 100 M 10 M 10 M Switch Switch Repeater Repeater Switch Switch

100 100 100 100 100 100

MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s

B M

Fast Ethernet Switch 100 MBit/s Fast Ethernet Switch M

0 1 1 Server Farm

End User Connection End User Connection

10 MBit/s 10 MBit/s 10 MBit/s 100 MBit/s 100 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s

10 M 10 M 10 M 100 M 100 M 10 M 10 M 10 M Switch Switch Switch Repeater Repeater Switch Switch Switch

100 100 100 100 100 100 100 100 Server Farm

MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s

B M

Fast Ethernet Switch 1000 MBit/s Fast Ethernet Switch M

1 1 Gigabit Ethernet Modules

Broadband Network Technologies IEEE 802.3 Ethernet 5 Migration (cont.) – Upgrading a Switched Backbone

End User Connection 100 MBit/s 100 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s

100 M 100 M 10 M 10 M 10 M 10 M Repeater Repeater Switch Switch Switch Switch

100 100 100 100 100 100 MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s

Fast Ethernet Switch 100 MBit/s Backbone

End User Connection

100 MBit/s 100 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s 10 MBit/s

100 M 100 M 10 M 10 M 10 M 10 M Repeater Repeater Switch Switch Switch Switch

1000 1000 1000 1000 1000 1000 MBit/s MBit/s MBit/s MBit/s MBit/s MBit/s

Gigabit Ethernet Switch or Repeater 1000 MBit/s Backbone

Broadband Network Technologies IEEE 802.3 Ethernet 5 IEEE 802.3 Ethernet – Summary

Comparison with other High-speed networks

Capabilities Gigabit Ethernet Fast Ethernet ATM FDDI IP Yes Yes Requires RFC 1557 or IP Yes Compatibility over LANE today, I-PNNI and/or MPOA in the future Ethernet Yes Yes Requires LANE Yes, though Packets 802.1h translation bridge Handle Yes Yes Yes, but application Yes Multimedia needs substantial changes Quality of Yes, with RSVP Yes, with RSVP Yes with SVCs or RSVP Yes, with RSVP Service and/or 8021p and/or 8021p with complex mapping and/or 8021p from IETF (work in progress) VLANS with Yes Yes Requires mapping LANE Yes 802,1q / 802.1p and/or SVCs to 802.1q

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel

• ANSI X3T9.3 standardized it in 1995 (started in 1988) – Designed to transport many protocols, such as FDDI, serial HIPPI, SCSI, Gigabit Ethernet, IP and others – Switched full duplex medium – Channels are established between the Originator and the Responder – Transfer rates from 100 Mbit/s to 3.2 Gbit/s – Distance up to 10 km (for single mode fiber) – Multi-layered stack of functional levels (not mapping directly to OSI) – Different topologies can be configured • point-to-point • arbitrated loop • switched fabric

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel (cont.)

• Lower two layers (FC-0 and FC-1) (almost) correspond to the 1000-Base-X PHY layer • Ethernet requires a lower laser linewidth and has a different data rate • Most common data rate is 100MByte/s=800Mbit/s=1063Mbaud • Up to 1063Mbaud copper (STP) can be used as well CHANNELS NETWORKS

FC-4 IPI HIPPI SCSI SBCCS IEEE 802.2 IP ATM

Common Services FC-3 1000 Base-X Gigabit Ethernet FC-2 Framing Protocol / Flow Control

FC-1 Encode / Decode

FC-0 133 Mbaud 266 Mbaud 531 Mbaud 1.06Gbaud 2.1 Mbaud 4.2 Mbaud

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel - Layers

•FC-0 – Specifies the physical link • Media, transmitters, receivers, connectors – Wide range of different technologies supported • STP, Video cable, 62.5µm and 50µm multimode fiber, single mode fiber – Open Fiber Control System (OFC) • Power the laser down if the fiber is open -> eye safety! •FC-1 – 8B/10B encoding • 8 bits of data are encoded in a 10 bit Transmission character • 4 Transmission characters make up a Transmission word • Running Disparity (RD) sums up the „1“s and „0“s and can be either positive or negative • Depending on the RD value, one of two possible Transmission characters is chosen for each data byte to achieve a DC free code • A special character marks the start of Ordered Sets (control sequences) – Start of Frame (SOF), End of Frame (EOF), Link Reset (LR), ...

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel - Layers

•FC-2 – Signalling protocol level – Defines frame structure – 32-bit CRC Start of Frame Optional End of Payload CRC Frame Header Header Frame

42424 0-2048 44 Size in bytes – Different Service classes: •Class 1 – Circuit switched connection •Class 2 – Frame switched, connectionless – ACK confirms the delivery of every frame •Class 3 – Frame switched, unconfirmed • Class 4 (fractional bandwidth) to 6 (Multicast) are largely undefined

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel – Layers (cont.)

Sequences and Exchanges • Sequence = Group of frames flowing in the same direction • Exchange = Group of sequences for a single operation • Protocol = 5 types of exchanges (N_Port Login, Fabric Login, N_Port Logout, Data transfer, Primitive Sequence)

INITIATOR RESPONDER Command Sequence

Acks Transfer Ready Data Sequence

Response Sequence

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel – Layers (cont.)

•FC-3 – Services for multiple ports on one node • Striping of hard disks • Hunt groups (more than port responds to the same alias address) •FC-4 – Defines application interfaces to Upper Layer Protocols (ULPs) • SCSI (Small Computer System Interface) • HIPPI (High Performance Parallel Interface) • IP (Internet Protocol) • AAL5 (ATM Adaption Layer) • IEEE 802.2

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel – Topologies

• Point-to-point – Consists of two FC devices connected – Full bandwidth all the time • Arbitrated Loop – Up to 127 ports in a single network – When a node wants to send, it has to gain control of the loop (ring) • Send out ARBx Signal with x= physical address of the node • Once it receives its ARBx back, it is allowed to send OPEN Signal (OPN) • Establishes point-to-point communication • All other nodes simply repeat the data – When more than one node want to send • Block the ARBy when y is higher than own x • Otherwise forward ARBy – Fairness algorithm prohibits a device from arbitrating again until others had the chance to arbitrate

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel – Topologies (cont.)

• Fabric – Connects up to 224 devices in a cross-point switched configuration – Provide parallel transmission – Originator gets a busy signal if not delivered – Relieve nodes from routing issues • Either set up a connection (for Class 1) • Or put responders address on the frame (Class 2) – Connect devices that run at different speeds – Provide cable matching

Broadband Network Technologies IEEE 802.3 Ethernet 6 Fiber Channel – Summary

• Fiber Channel provides – 800 Mbit/s over 10s of km between millions of users – Support for various transmission media – Point-to-point, loop, switched fabrics – From 100Mbit/s to 3.2 Gbit/s – SCSI, HIPPI, LAN card replacement • Fiber Channel drawbacks – Jungle of standards (over 20 different standards) – No real shared medium

Broadband Network Technologies IEEE 802.3 Ethernet 6 IEEE 802.3 Ethernet – Acronyms

AUI Attachment Unit Interface PAD Packet Assembler / Disassembler BNC Baby N Connector PAR Project Authorisation Request CD Carrier Detection PCS Physical Coding Sub-Layer CRC Cyclic Redundancy Check PMA Physical Medium Attachment CSMA Carrier Sense Multiple Access PLS Physical Signalling Sub-layer DIX DEC, Intel, Xerox SAP Service Access Point DTE Data Terminal Equipment VG Voice Graded FLP Fast Link Pulses FOIRL Fibre Optic Inter-Repeater Link GMMI Gigabit Media Independent Interface HSSG Higher Speed Study Group LLC Logical Link Control MAC Medium Access Control MDI Medium Dependent Interface MAU Medium Attachment Unit MII Medium Independent Interface NRZ Non-Return to Zero NRZI Non-Return to Zero Inverted

Broadband Network Technologies IEEE 802.3 Ethernet 7 IEEE 802.3 Ethernet – References

Antol Badach, Olaf Knauer, Erwin Hoffmann: High Speed Networks, Addison Wesley, Reading, Massachusetts, 2. Auflage 1997 ISBN: 3-8273-1232-9 Andrew S. Tanenbaum: Computer Networks, Prentice Hall International, Third Edition, 1996 ISBN: 0-13-394248-1 David G. Cunningham, William G. Lane: Gigabit Ethernet Networking Macmillan Technical Publishing, USA, 1999 ISBN: 1-57870-062-0 Switched Ethernet http://jmazza.shillsdata.com/tech/ethernet/switched

Ethernet and Fast Ethernet Guide http://www.ots.utexas.edu/ethernet

100Base-T Migration Guide http://www.3com.com/nsc/100208.html

Broadband Network Technologies IEEE 802.3 Ethernet 7 IEEE 802.3 Ethernet – References (cont.)

Desktop ATM vs. Fast Ethernet http://www.networking.ibm.com/atm/atm25fe.html

Gigabit Ethernet Information (PAR, Drafts) http://www.ots.utexas.edu:8080/ethernet/descript-gigabit-ieee.html

Gigabit Ethernet Technical Overview http://www.nbase.com/notes/gigabit.html

Gigabit Ethernet Alliance http://www.gigabit-ethernet.org

Broadband Network Technologies IEEE 802.3 Ethernet 7