The crossbar network is the easiest interconnection network. It has a two dimensional grid of switches. It is a non-blocking network and give connectivity among inputs and outputs and it is possible to connect any of the inputs to any output.
An N * M crossbar network is given in the following Figure 3 (a) and switch connections are given in Figure 3 (b)
A switch positioned at a cross point of a particular row and column. Connects that particular row (input) to column (output).The hardware cost of N*N crossbar switch is proportional to N2. It makes delay equivalent to single switching operation and the routing control mechanism is simple. The crossbar network needs N2 switches for N input and N output network.