Introduction to Asynchronous Transfer Mode:

It is very high speed mode of transfer. Its cost is very low. It can be used for transmission of data, voice, video and television. It gives speed up to 155 mbps to 622 mbps. It uses cell switching technique.  It used in large infrastructure where they requirehigh data speed. It has very high bandwidth. It uses small packets to transmit information. They are very easier and provide much more flexibility.

An every ATM cell contains 5 byte header and 48 byte information. ATM is mainly of two types, first virtual path; it is a bundle of network which is switched across the ATM. Second, virtual channels, they are bundle of VPs; they connect to create a transmission path.

ATM architecture contains four layers, first layer is divided into two parts that is higher layers, next layer is ATM adaptation layer, then ATM layer which is again divided into two parts, virtual layer and virtual path, and the last layer is physical layer, it determines the speed of data. They also have three separate planes. User plane, it provides user information, control plane, and management plane.

ATM adaptations layers: ATM services are divided into four parts: CLASS A and B are connection orientated with time relation, where CLASS C with no time relation, and last CLASS D connection less with no time relation.

There are AALs are defined: AAL0, AAL1, AAL2, AAL3/4, AAL5 

It can used to make connection either point-to-point or point-to-multipoint. Point-to-points are unidirectional or bidirectional whereas point-to-multipoint is unidirectional only.

Advantages of ATM:

–          It gives bandwidth on demand,

–          Support all multimedia applications

–          Support both real and non-real time application

–          Flexible and gives network for infrastructure.

Download Seminar Topics for CSE on Asynchronous Transfer Mode.