Fast Ethernet Networking Technology(Ieee 802

FAST ETHERNET NETWORKING TECHNOLOGY(IEEE 802.3u)

INTRODUCTION:

10B Ethernet Technology cannot support modern high speed applications such as 3-D images and Multimedia services
Fast Ethernet technology was designed to meet the demands of high speed multimedia applications
Companies currently using 10B technology can easily upgrade to to FAST Ethernet, which offers a data rate of 100 Mbps
Fast Ethernet is an extension of the Ethernet standards with 100 Mbps data rate, using the Ethernet protocol. It uses CSMA/CD
An existing 10B network can be easily upgraded to 100BT LAN with the addition of a few switching devices

FAST ETHERNET CABLING:

Uses either UTP or Fiber
There are 3 versions of Fast Ethernet

(1)100BT4(2) 100BTX (3) 100BFX

100BT4:

100 stands for 100 Mbps, B stands for baseband signal, T stands for twisted pair and 4 stands for four pairs. Thus 100BT4 uses 4 pairs of twisted wiring
It is FDX
Uses 4 pairs of CAT 3 UTP. CAT 4 or 5 can also be used.
Uses RJ-45 Connector
Pairs 3 and 4 are used for data transmission.
One wire from pair 1 and one wire from pair 2 are used for CSMA/CD
Each pair transmits data at 33.33 Mbps, giving an overall rate of 100 Mbps
8B6T code is used to convert 8 bits into 6 bit
This reduces the effective data rate of each pair to 25 Mbps.
This was necessary since the CAT 3 wiring can support only upto 30Mbps not 33.33MBps

100BTX:

100 Mbps, Baseband signal, but uses only two pairs of CAT 5 UTP or LAT 1 – STP
HDX
CAT 5 can handle upto 100 Mbps
Uses 4B/5B encoding

100BFX:

100 Mbps, Baseband Signal, FX stands for fiber
FDX
Uses one pair of Multimode fiber 62.5/125 with SC connector
Uses 4B/5B encoding with NRZ-I voltage levels

Fast Ethernet Repeaters:

Two Types:

Class 1:

Converts the Line signals from the incoming port to digital signal (notice this is an example of Digital to Digital Conversion- a digital signal of one form is converted into a digital signal of another format)
Allows different types of Fast Ethernet Technologies to be connected to the LAN Segment. For example, you can connect a 100BTX station and a 100BFX stations using a Class 1 Switch as Shown below

Only one class 1 repeater can be used in a Fast Ethernet Segment

Class I I Repeaters:

A class to repeater repeats the incoming signal, sending it to every other port on the repeater.
Used for connecting the same type of Fast Ethernet Media i.e either 100BTX or 100 B FX
Only 2 permitted /segment as shown

Fast Ethernet Diameter:

Network Diameter is a term used to describe the distance between two end stations connected through a Repeater or a Switch.
It is a function of the propagation delay (the difference between the transmission time and the receiving time ) caused by the cables, NIC, and Repeater.
Defined in terms of BIT TIME ( time for 1 BIT)
Fast Ethernet bit time =1/108 Seconds
In Ethernet Network, propagation delay is = 512 bit time, since the first bit of the frame must reach the destination before the last bit is transmitted by the source.
To Calculate the Network Diameter , the total propagation delay of the Network Components must be less than 512 bit time.
Fig below shows the Propagation Delay of Various Fast Ethernet Components

Component /

BIT TIME

2 TX or FX NICS

2 T4 NICS

1 T4 , 1 TX NIC
1 TX and 1 FX NIC
100 m of CAT 3 UTP
100 m of CAT 4 UTP
100 m of CAT 5 UTP
100 m of STP
Class I repeater
Class I I repeater / 100
138
127
127
114
114
111
111
140
92

The diameter of a FAST Ethernet using 100BTX or 100 B T4 is 204 meter
The table below shows the Maximum diameters for various situation

Type of Repeater

/ 100BTX/100BT4 / 100BFX
HOST-To-HOST connection (without repeaters)
One Class I repeater
One Class II repeater
Two Class II repeaters / 100m
200m
200m
205m / 412m
272m
320m
N/A

Following information can be used to determine the diameter of a Fast Ethernet

(a)The maximum distance between two repeaters using UTP = 5m

(b)The maximum length of all UTP Cable is 100m

(c)The maximum distance between a repeater and a switch is 1000m

(d)The maximum distance between 2 Switches connected by a fiber is 2000m

Figs Below show various connections

100m UTP100m UTP

100m UTP 5mUTP 100m UTP

Expanding Fast Ethernet:

Since Fast Ethernet allows only two repeaters, only way to expand the Fast Ethernet is to use a Switch
Fig below shows expansion of Fast Ethernet using switch

10/100Mbps operation

Note that most 100 Mbps cards can also operate at 10Mbps when connected to a 10BT HUB.
Thus 10 Mbps stations can still operate on a 100 Mbps Network
Most Hubs also operate at 10 or 100 Mbps dual speed (See Fig)

Giga bit Ethernet Networking

Introduction:

GB Ethernet is a new technology that is compatible with Ethernet and Fast Ethernet, and it has become a dominant technology for the backbone with GB Switches
DB Ethernet is used for campus or company Headquarter backbone
The GB Ethernet is capable of handling all types of data transmission such as voice, Data and Video and Multimedia
This technology is possible because of availability of high speed PCI buses and high speed CPUs. For example a 64 bit PCI bus runs at 100 MHZ and can transfer data at up to 6.4 GBPS
By adding Quality of Service (QoS) , the GB Ethernet will be the Next Generation of the LAN and Campus backbones

Characteristics of GB Ethernet:

GB Ethernet is used to connect Ethernet and Fast Ethernet Switches and for interconnecting High Speed Servers
GB Ethernet allows corporations and organizations to to upgrade their Network to 1000 MBPS ( 1 GBPS) while using the same Operating System and same application software
Operates at 1000 Mbps
Uses IEEE 802.3 frame format
Uses IEEE 802.3 maximum frame parameters
Supports FDX and HDX operation
Uses CSMS/CD for HDX and supports one repeater per collision domain
Uses fiber and copper wire
Supports 200 m diameter

GB Ethernet Network Componenets:

(a)GB Ethernet NIC

(b)Switches 100Mbps/1000 Mbps

(c)GB Ethernet repeaters

(d)GB Switch

GB Ethernet Protocol Architecture:

Fig on the Next page shows GB Ethernet protocol Stack

Physical Interface layer:

Defines the physical characteristics of the interface media, connector type, cable type, Transmitter and receiver characteristics Etc. Offers 4 varieties

(1)1000BLX: - Designed for Long Wave LASER (LW) over SM and MM Fiber at a wavelength of 1300nm up to 5 KM . Used for long distance transmission. For SM fiber 9/125, MM fiber 50/125

(2)1000 BSX : -Designed for Short Wave ( SW) LASER at 850nm over MM fiber. 50/125, 62.5/125. Used for short distances – upto 500 meter

(3)1000 BCX: - Uses Twin ax cable ( 150 ohm balanced shielded cable. Supports 9 pin D- connector

(4)1000BT: - Uses 4 pairs of CAT 5 or CAT 6 UTP cable with RJ-45 connector. 4 pairs of UTP upto 100 meter

Serializer/Deserializer:

At the TX side, accepts data in parallel from the 8B/10B encoder and converts it into serial form
At the RX side, accepts serial data from the physical layer and converts it into parallel form for the 8B/10B encoder

8B/10B Encoder/Decoder:

Used for Fiber optic transmission. Converts 8bit data into 10 bit code

MAC LAYER:

GB Ethernet supports both HDX and FDX operation
HDX uses CSMS/CD for Media Access
FDX operation uses 802.3x point to point connection protocol
GB Ethernet uses a minimum frame size of 512 bytes by adding carrier extension to the frame as shown below.

Min 64 bytes for regular Ethernet

Min 512 Bytes for GB Ethernet

FDX Transmission:

In FDX signals travel in both directions simultaneously
The Data rate is therefore doubled
FDX is used only in point –to – point configuration
Requires a FDX Switch as shown

MAC AND PHYSICAL LAYER ARCHITECTURE:

Fig below shows the GB Ethernet Architecture

8 bit bus

8 BIT BUS

100 m UTP

SMFMM Fiber Twin ax cable

5KM 500 M 25 meter

GB WORK STATIONS

GB Ethernet Diameter:

GB Ethernet does not support Repeaters
GB Ethernet supports point to point connection using Fiber Optic cable, twinax cable or UTP cable
In GB Ethernet, the Network Diameter can be extended by using only the GB Ethernet Switches
Table below shows GB Ethernet cable types and distances

Standard / Cable type / Diameter
(Microns) / Modal BW
MHZKM / Distance
(Meters)
1000BSX / MMF / 62.5 / 160 / 220
MMF / 62.5 / 200 / 270
MMF / 50 / 400 / 500
MMF / 50 / 500 / 550
1000BLX / MMF / 62.5 / 500 / 550
MMF / 50 / 400 / 550
MMF / 50 / 500 / 550
SMF / 9 / 5000
1000BCX / Twinax / 25
1000BT / UTP CAT 5e
Or
CAT 6 / 100

Buffered Distributer Device :

It is a FDX multiport HUB
It connects several GB Ethernet together
Operates like a Repeater, except it stores GB Ethernet frames and then broadcast the frame to all other ports of the device.
Capable of storing more than one frame in its buffer before forwarding.

GB Ethernet Applications:

Most organizations are currently using regular Ethernet or Fast Ethernet, which can be easily upgraded to GB Ethernet.
GB Ethernet is used for Campus ( e.g a Company, College or University ), Corporate Headquarters or buildings that require very high Data Rates for high end graphics, Multimedia Applications, Voice/Data/Video Integration Etc.
GB Ethernet Applications are

(a)Switch – to - Switch

(b)Switch – to – Server

(c)Repeater – to – Switch

(a)Upgrading Fast Ethernet Switch to GB Ethernet Switch and installing GB Ethernet cards in high Speed Server as shown in the fig below

100MBPS100 MBPS1000MBPS

CARD CARD CARD

(b)Upgrading a Switch to a Server link at 1000Mbps:

1000 MBPS LINK

100 MBPS10 MBPS 100

1000 MBPS1000MBPS1000MBPS

10 MBPS WS100 MBPS WS1000 MBPS

(d) Upgrading the Switch to Switch Link:

Hyder KhojaPage 110/06/2018