Rip Operation; Rip Versions; Supported Rip Features - HPE FlexNetwork HSR6800 Configuration Manual

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Poison reverse—Enables RIP to set the metric of routes received from a neighbor to 16 and
sends back these routes to the neighbor so the neighbor can delete such information from its
routing table to prevent routing loops.
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Triggered updates—RIP immediately advertises triggered updates for topology changes to
reduce the possibility of routing loops and to speed up convergence.

RIP operation

RIP works as follows:
RIP sends request messages to neighboring routers. Neighboring routers return response
1.
messages containing routing tables.
RIP uses the received responses to update the local routing table and sends triggered update
2.
messages to its neighbors. All RIP routers on the network do this to learn the most recent
routing information.
RIP sends the local routing table to its neighbors every 30 seconds. After a RIP neighbor
3.
receives the message, it updates its routing table, selects optimal routes, and sends an update
to other neighbors. RIP ages routes to keep only valid routes.

RIP versions

There are two RIP versions, RIPv1 and RIPv2.
RIPv1 is a classful routing protocol. It advertises messages through broadcast only. RIPv1
messages do not carry mask information, so RIPv1 can only recognize natural networks such as
Class A, B, and C. For this reason, RIPv1 does not support non-contiguous subnets.
RIPv2 is a classless routing protocol. It has the following advantages over RIPv1:
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Supports route tags to implement flexible route control through routing policies.
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Supports masks, route summarization, and CIDR.
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Supports designated next hops to select the best ones on broadcast networks.
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Supports multicasting route updates so only RIPv2 routers can receive these updates to reduce
resource consumption.
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Supports simple authentication and MD5 authentication to enhance security.
RIPv2 supports two transmission modes: broadcast and multicast. Multicast is the default mode
using 224.0.0.9 as the multicast address. An interface operating in the RIPv2 broadcast mode can
also receive RIPv1 messages.

Supported RIP features

The current implementation supports the following RIP features:
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RIPv1 and RIPv2
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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.
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RIP FRR
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BFD
RIP periodically sends route update requests to neighbors. If no route update response for a route is
received within the specified interval, RIP considers the route unreachable. This mechanism cannot
detect link faults quickly. After BFD is configured for RIP, and BFD detects a broken link, RIP can
quickly age out the unreachable route, thus avoiding interference to other services.
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