index.md (871B)
1 +++ 2 title = "Network: overview" 3 +++ 4 5 # Network: overview 6 The layer answers: 7 8 - how to get from A to B 9 - how to prevent network congestion 10 - how to provide quality of service 11 - how to connect multiple networks together 12 13 layers below it don't know about end-to-end delivery 14 layers above it don’t know about the network topology 15 nobody knows anything about routing — it’s the network layer’s job 16 17 **Service types — connectionless v.s. connection-oriented** 18 19 | | | 20 | --- | --- | 21 | Connectionless | Connection-oriented | 22 | - routers use algorithms for routing to send each packet individually<br>- used by IP<br> | - fixed route decided when a connection is made<br>- all packets go along that route<br>- sometimes used by ISPs on top of IP<br> |