Routing Information Protocol (RIP)

Routing Information Protocol (RIP)

• Designed for use on smaller networks
• Dynamic routing protocol
• Oldest distance-vector routing protocols
• RIP uses the Bellman-Ford Distance Vector algorithm to determine the best “path” to a particular destination
• Which employ the “Hop count” as a routing metric to find the best path between the source and the destination network
• Routes with lower hop counts are preferred
• Maximum hop count of 15 hops, any network that is 16 hops away or more is considered unreachable to RIP
• If multiple paths exist to a particular destination, RIP will load balance between those paths (by default, up to 4) only if the metric (hop count) is equal
• RIP sends out periodic routing updates (every 30 seconds)
• RIP sends out the full routing table every periodic update
• RIP routes have an administrative distance of 120.

RIP Versions:

1. Version 1 (RIPv1)

2. Version 2 (RIPv2)

• Unless RIPv2 is manually specified, a Cisco will default to RIPv1 when configuring RIP
• RIPv1 routers will sent only Version 1 packets
• RIPv1 routers will receive both Version 1 and 2 updates
• RIPv2 routers will both send and receive only Version 2 updates

RIP Timers:

1.            Update Timer (default 30 seconds) – Routing table update.

2.            Invalid Timer (default 180 seconds) – Interval of time (in seconds) after which a route is    declared invalid

3.            Hold-down Timer (default 180 seconds)

4.            Flush Timer (default 240 seconds) – After expire route entry deleted form routing table.