Network Space Division Switching Techniques

In space division switching, the paths in the circuit are separated with each other spatially that is different ongoing connections at a same instant uses different switching paths, which are separated spatially. Crossbar switches and multistage space division switches are example of space division switching.

 Time division switching

Time division switches use time division multiplexing to achieve switching. There two methods used in time division switching: time slot interchange and TDM bus.

Time slot interchange (TSI)

We are using the following example to discuss TSI and TDM,

Assume that we have four nodes at sending side and four nodes at receiving. The nodes are labeled  as shown below,

Time division multiplexing

The above figure shows the results of ordinary time-division multiplexing. Data are received at the same order as they are send, data from 1 go to 1, data from 2 to go to 2, from 3 to go to 3 and from 4 go to 4. If we want to send the data in the following order, it is not possible with time division multiplexing,

1 to 3

2 to 4

3 to 1

4 to 2

In this type of situations, we use time slot interchange techniques 

Time slot interchange

Here we insert a device called a time slote interchange into the link. TSI changes the ordering of the slots based on the desired connection. 

Next : Message Switching

Previous :  Switching in Computer Networks
Index :   Computer Networks and Communication online coaching