Discuss the csma/cd and csma/ca protocols, Computer Engineering

Assignment Help:

Discuss the CSMA/CD and CSMA/CA protocols.

CSMA/CD: this is an access method used mainly with LANs configured in a bus topology. Along with CSMA/CD, any station (node) can send a message to another station (or stations) as long as the transmission medium is free of transmissions from another station. Stations monitor (listen to) the line to find out if the line is busy. If the station has a message to transmit but the line is busy, this waits for an idle condition before transmitting message of this. If two stations transmit at similar time, collisions arise. When this occurs, the station first sensing the collision sends a special jamming signal to all other stations on the network. All stations then cease transmitting (back off) and wait a random period of time before attempting a retransmission. The random delay times for all stations are different, and therefore, permit for prioritizing the stations on the network. If successive collisions happen, the back off period for every station is twice. Along with CSMA/CD stations should contend for the network. A station has not guaranteed access to the network. To notice the occurrence of a collision, a station must be capable of transmitting and receiving simultaneously. CSMA/CD is used with most LANs configured in a bus topology. Ethernet is an illustration of a LAN which uses CSMA/CD.

CSMA/CA: this belongs to a class of protocols termed as multiple access methods. CSMA/CA stands for: Carrier Sense Multiple Access with Collision Avoidance. In Carrier Sense Multiple Access, a station wishing to transmit has to primary listen to the channel for a predetermined amount of time therefore as to check for any activity on the channel. If the channel is sensed "idle" then the station is allowed to transmit. If the channel is sensed like "busy" the station has to defer its transmission. It is the essence of both CSMA/CA and CSMA/CD. In CSMA/CA (Local Talk), a station sends a signal telling all other stations not to transmit only one time the channel is clear then sends its packet. In Ethernet 802.3, the station carries on to wait for a time and checks to observe if the channel is even free. If this is free, the station transmits, and waits for an acknowledgment signal which the packet was received.


Related Discussions:- Discuss the csma/cd and csma/ca protocols

What is ai, Artificial intelligence ("AI") can mean a lot of things too man...

Artificial intelligence ("AI") can mean a lot of things too many people. Much confusion arises that the word 'intelligence' is ill-defined. The phrase is so broad that people have

Explain the term - integrity, Explain the term - Integrity In most c...

Explain the term - Integrity In most cases, corporate data should remain unchanged by third parties, so the system should be capable of ensuring that only authorised personn

What is file scope, Explain File scope File scope: The variables and ...

Explain File scope File scope: The variables and functions with file scope appear outside any block or list of parameters and are accessible from any place in the translation

What is the necessity of an interface, What is the necessity of an interfac...

What is the necessity of an interface?  Any device that has to be linked to a CPU requires an interface. This takes care of the mismatch in speed, data and electrical character

Need of the assembly language, Q. Need of the assembly language ? Machi...

Q. Need of the assembly language ? Machine language code comprises the 0-1 combinations which computer decodes directly.  Though the machine language has the following problems

Networking, Nyquist''s sampling theorem says "if you have a signal that is ...

Nyquist''s sampling theorem says "if you have a signal that is perfectly band limited to a bandwidth of f0 then you can collect all the information there is in that signal by sampl

Explain about wide area network, Q. Explain about Wide Area Network? Wi...

Q. Explain about Wide Area Network? Wide Area Network (WAN) usually refers to a network, which covers a large geographical area as well as use communications subnets (circuits)

How to input to circuit, Q. How to input to circuit? Register A bit...

Q. How to input to circuit? Register A bits as a0, a1, a2 and a3 in the corresponding X bits of the Full Adder (FA). Register B bits as given in the Figure above as in

Discuss in brief the history of e-commerce, Discuss in brief the history of...

Discuss in brief the history of E-Commerce. History of E-commerce illustrated below: E-commerce began before personal computers were prevalent and has grown into a multibill

What is the prominence of rs232-c in serial communication, What is the prom...

What is the prominence of RS232-C in serial communication?  Name some application where you see its use.  RS-232 stands for Recommend Standard number 232 and C is the latest re

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd