Packet-switched networks: routing
Goal: move packets among routers from source to destination
- we’ll study several path selection algorithms (chapter 4)
datagram network:
- destination address determines next hop
- routes may change during session
- analogy: driving, asking directions
virtual circuit network:
- each packet carries tag (virtual circuit ID), tag determines next hop
- fixed path determined at call setup time, remains fixed thru call
- routers maintain per-call state