1. Failure: when a node or a trunk fails, it can no longer be used as a part of the rout.2. Congestion: when a particular portion of the network is heavily congested , it is desirable to route packets around rather than through the area of congestion.
circuit switching
In a network switching subsystem, a mobile switching center is the centerpiece. The function of the mobile switching center is to perform the telephony switching functions and serves as a network node.
there are three types of switching techniques 1) circuit switcching 2) Packet switching 3)Message switching
Ethernet
switching complexity
it is very cheap
PSTN
Packet-switching
Switching channels on the router or access point will reduce interference on a network.
carrying user voice and data circuit switching packet switching
packet switching
Packet-switching