Presentation

On

Sub:

ETHERNET AND TOKEN

RING

CN4nd Sem Computer

(2016-17)

Prepared By:

Name: Shail M. Nakum

Enr. No: 150410107054

Class: S.Y. : Computer

Div.-I

CONTENTS

• ETHERNET

• TOKEN RING

ETHERNET

•Ethernet is the most widely-installed local area network (

LAN) technology.

•Specified in a standard, IEEE 802.3, Ethernet was

originally developed by Xerox from an earlier specification

called Alohanet and then developed further by Xerox, DEC,

and Intel.

•An Ethernet LAN typically uses coaxial cable or special

grades of twisted pair wires.

•The most commonly installed Ethernet systems are called

10BASE-T and provide transmission speeds up to 10 Mbps

•The Fast Ethernet standard (IEEE 802.3u) has been

established for Ethernet networks that need higher

transmission speeds.

•This standard raises the Ethernet speed limit from 10

Mbps to 100 Mbps with only minimal changes to the

existing cable structure.

•Fast Ethernet provides faster throughput for video,

multimedia, graphics, Internet surfing and stronger error

detection and correction.

•Gigabit Ethernet was developed to meet the need for faster

communication networks with applications such as

multimedia

•The most important differences between Gigabit Ethernet

and Fast Ethernet include the additional support of full

duplex operation in the MAC layer and the data rates.

•10 Gigabit Ethernet is the fastest and most recent of

the Ethernet standards. IEEE 802.3ae defines a

version of Ethernet with a nominal rate of 10Gbits/s

that makes it 10 times faster than Gigabit Ethernet.

TOKEN RING

A Token Ring network is a local area network (LAN) in which all

computers are connected in a ring or star topology and a bit- or

token-passing scheme is used in order to prevent the collision of

data between two computers that want to send messages at the same

time. The Token Ring protocol is the second most widely-used

protocol on local area networks after Ethernet. The IBM Token Ring

protocol led to a standard version, specified as IEEE 802.5. Both

protocols are used and are very similar. The IEEE 802.5 Token Ring

technology provides for data transfer rates of either 4 or 16

megabits per second.

Very briefly, here is how it works:

•Empty information frames are continuously circulated on

the ring.

•When a computer has a message to send, it inserts a token

in an empty frame (this may consist of simply changing a 0

to a 1 in the token bit part of the frame) and inserts a

message and a destination identifier in the frame.

•The frame is then examined by each successive

workstation. If the workstation sees that it is the

destination for the message, it copies the message

from the frame and changes the token back to 0.

•When the frame gets back to the originator, it sees

that the token has been changed to 0 and that the

message has been copied and received. It removes the

message from the frame.

•The frame continues to circulate as an "empty" frame, ready to

be taken by a workstation when it has a message to send.

•The token scheme can also be used with bus topology LANs.

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