Asynchronous or statistical time division multiplexing, Computer Networking

Assignment Help:

Asynchronous or Statistical Time Division Multiplexing

As we  have seen  synchronous  TDM does not  guarantee that the full capacity of a link in sued. In fact it is more likely  that only  a portion of the  time slots are in use at a given  instant. Because  the time  slots  are reassigned and  fixed whenever a connected device is not  transmitting, the  corresponding  slot is empty and that much   capacity of the path  is wasted. For  example imagine that we have multiplexed the output of 20 identical computer onto a single line. Suing synchronous TDM the speed  of that line must be at  least 20 times the speed of each input line. But  what  if only 10 computers  are in use at a time ? half of the capacity  of the line  is wasted.

Statistical  time  division  multiplexing is designed to avoid this type of waste. As with  the term  synchronous. The term  asynchronous means some  things   different  in multiplexing  that it  means  in other  areas of data communications. Here it  flexible  or not  fixed.

Like synchronous TDM asynchronous TDM allows  a number of lower  speed  input  lines  to be  multiplexed  to a single  higher speed  line. Unlike  synchronous  TDM however in asynchronous TDM the total  speed of the input  can be greater than  the capacity  of the path. In a synchronous systems if we have in  input  lines. The frame contains a fixed number of a least m time  slots. In  an asynchronous systems. If  we have  n input line the  frame contains no more  than  m slots with m less than n. In  this way asynchronous TDM supports  the same  number of input lines as synchronous TDM with a lower capacity  link or given the same  link. Asynchronous TDM can support more  devices  than  synchronous TDM.

1558_Asynchronous or Statistical Time Division Multiplexing.gif

figure Asynchronous TDM

The number  of time  slots in an asynchronous TDM fame is based on a statistical analysis of the number  of input lines that are likely to be transmitting at any given  time. Rather than being reassigned each slot  is available to any  of the attached input lines  that has data  to seen. The  multiplexer scans the input lines accept portions of data until a frame is felled and then sends the frame across the link. If  there are not enough data to  fill all the  slot s in a frame the frame a transmitted only partially filled thus full link capacity  may not be used 100 percent   of the time. But  the ability to allocate time slots  dynamically coupled with  the lower  ration of the slots  to input  greatly reduces the likelihood and degree  of waste.

 

 


Related Discussions:- Asynchronous or statistical time division multiplexing

Explain anti-aliasing techniques, Question: (a) Explain the issue assoc...

Question: (a) Explain the issue associated with vertices when the scan line scan line polygon fill algorithm is being applied? (b) Explain the logic of shortening edges to a

Describe the sequence of events occur in host attempt, The following inform...

The following information was obtained from a host: IP address...............205.133.127.8/24 Default Gateway...... 205.133.127.1 DNS Server.............139.100.110.10

Approach for client - server communication, Client Once the GUI applicat...

Client Once the GUI application is loaded, it will send a request (instance/object of Commands class) to server for a list of files from the server's shared directory.Client wil

Lan hardware and packet filtering, LAN HARDWARE AND PACKET FILTERING: ...

LAN HARDWARE AND PACKET FILTERING: The diagram below explain the LAN hardware LAN INTERFACE:  LAN interface operates all details of frame reception and transmis

Applications of fiber optics, Applications of Fiber Optics - Backbone ...

Applications of Fiber Optics - Backbone networks because of wide bandwidth and cost effectiveness - Cable TV - LANS - 100Base-FX (Fast Ethernet)

Explain how reducing ineffective taxation, Question: (a) With mobile t...

Question: (a) With mobile telecommunications providing an important engine for growth, continuing to stimulate growth and to ensure mobiles remain affordable for all, will re

What is transmission control protocol, Q. What is Transmission Control Prot...

Q. What is Transmission Control Protocol? Transmission Control Protocol TCP Services - Stream delivery service Permits the sending process to deliver data as a stream

Critical path method, You are the Senior Project Manager in a software comp...

You are the Senior Project Manager in a software company and have, as part of your team, a student on a three month internship. The student has proudly told you that they have stu

List all application layer and transport layer protocols, a)  A host is sen...

a)  A host is sending a HTTP request to a HTTP server. In the table below, propose a correct set of source and destination port numbers for segments sent from host to server and fr

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