IP Routing

IP Routing

1. IP Address

   • Identifies a host or device in the Internet or other network

2. Networks

   • Address
     • First part of a host’s IP address.
   • SubnetMask
     • defines which bits identify the network and which identify the individual host
   • ClassFull Networks
     • Class A
       • 1.0.0.0 to 126.0.0.0
     • Class B
       • 128.0.0.0 to 191.255.0.0.
     • Class C
       • 192.0.0.0 to 223.255.255.0
     • Class D
       • 224.0.0.0 to 239.255.255.255.

3. Routing Table

   • Destination Network Address
     • Matches the packet’s destination IP address
   • Next-Hop Address
     • address of the next directly-connected device en route to the destination address
   • Subnet Mask
     • Defines how many bits the router examines when matching the two addresses
   • Forwarding Interface
     • instruct the router how to forward packets that match the destination address for the route.
   • Administrative Distance
     • compare routes learned by different routing protocols
   • Metric
     • compare routes learned by the same routing protocol

4. Static Routing

   • Routes that manually add to the routing table.

5. Dynamic Routing

   • RIP versions 1 and 2
   • Open Shortest Path First (OSPF) version 2
   • Border Gateway Protocol (BGP) version 4

6. Load Sharing

   • Enables the router to use redundant connections to the same remote site
   • Code to enable
     • ip load-sharing [per-destination | per-packet]
   • Configuration
     • Per destination
     • Per packet

7. Fast Caching

   • Designed to speed processing of packets that follow often-used routes
   • Enabling fast caching
     • Process switching
     • Fast Caching