computer network

Question

switching is of 3 type

1:circuit switching

2:packet switching(a:datagram       b:virtual circuit)

3:message switching

i am confused now that why datagram works at network layer and circuit switching at physical layer??

Answer 1

Packet switching is store and forward network. router buffer packet until it receives completely and then forward it. But in circuit switching first connection is established and then data transfers. you can imagine ckt switching with old telephone network.