Network Layer Flashcards
Main idea
Provides addressing
Four essential processes
- Addressing
- Encapsulation: creates packet with addressing info
- Routing: selects best path for and directs packets toward destination
- Decapsulation
IP use..
Is media independent; only packet size matters (maximum transmission unit)
Broadcast
A message sent from one host to all other hosts on network
Gateway router…
Delivers data to devices on remote network
Network layer supplies…
Network portion of address (this is how routers forward addresses between networks)
Hierarchical addressing
More subnets = fewer hosts
Network portion is the same
Default gateway
Forwards packets outside local network
Next hop address
Where to forward packet next; address of device that will process the packet next.
Ipconfig
View IP address of default gateway
No packet can’t be forwarded without a route
Forwarding process is known as routing
Only indicates the next hop router to be forwarded, not final router
Three main features of routing table:
Destination network
Next hop address
Metric
Routing table commands
Netstat -r, route, routePRINT
Default route
Matches all destination networks
0.0.0.0
Packet forwarding
- Layer 2 address is discarded for examination
2. Router at each hop only knows address of next hop
