R2511-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V5)

• Because the periodic update delivery is canceled, an acknowledgement and retransmission

mechanism is required to guarantee successful updates transmission on WANs.

Message types

RIP uses the following new types of message which are identified by the value of the command field:

• Update request (Type-9)—Requests the needed routes from the neighbor.

• Update response (Type-10)—Contains the routes requested by the neighbor.

• Update Acknowledge (Type-11)—Acknowledges received update responses.

TRIP retransmission mechanism

• If the router receives no update responses within a specified interval after sending an update

request, it sends the request again. If the router still receives no update response after the upper limit

for sending requests is reached, it considers the neighbor unreachable.

• If the router receives no update acknowledge within a specified interval after sending an update

response, it sends the update response again. If the router still receives no update acknowledge

after the upper limit for sending update responses is reached, it considers the neighbor

unreachable.

Supported RIP features

The current implementation supports the following RIP features:

• RIPv1 and RIPv2

• RIP support for multi-VPN-instance

RIP can serve as the IGP running between CE and PE on a BGP/MPLS VPN network. For related

information, see MPLS Configuration Guide.

• TRIP

• BFD

RIP detects route failures by periodically sending requests. If it receives no response for a route within a

certain time, RIP considers the route unreachable. This detection mechanism is not fast enough. To speed

up convergence, enable BFD for RIP.

Protocols and standards

• RFC 1058, Routing Information Protocol

• RFC 1723, RIP Version 2 - Carrying Additional Information

• RFC 1721, RIP Version 2 Protocol Analysis

• RFC 1722, RIP Version 2 Protocol Applicability Statement

• RFC 1724, RIP Version 2 MIB Extension

• RFC 2082, RIPv2 MD5 Authentication

• RFC 2091, Triggered Extensions to RIP to Support Demand Circuits

• RFC 2453, RIP Version 2