Week 5 - Routing Between Networks

Routers and multiple networks

• when PCs are on the same network they can communicate, but what about when they are on different networks?
• routers have multiple NICs, so they have interface on multiple networks
• a router connected to multiple networks can pass packets between them

it can only see what it is directly connected to

• to connect multiple routers that each have networks of their own, a higher-level network needs to be made to connect the routers

Routing tables

• routing tables correlate network addresses to the routers' networks
• they tell routers that other networks exist and how long it takes to get there.