H3C Technologies H3C SR8800 - Manual (Page 41)

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NOTE:
RIPv2 has two types of message transmission: broadcast and multicast. Multicast is the default type using
224.0.0.9 as the multicast address. The interface working in the RIPv2 broadcast mode can also receive
RIPv1 messages.
RIP message format
A RIP message consists of a header and up to 25 route entries. (A RIPv2 authentication message uses the
first route entry as the authentication entry, leaving 24 available.)
RIPv1 message format
Figure 6 RIPv1 Message Format
Header description:
• Command—Type of message. 1 indicates request, which is used to request all or part of the routing
information from the neighbor; 2 indicates response, which contains all or part of the routing
information. A response message consists of up to 25 route entries.
• Version—Version of RIP, 0x01 for RIPv1.
• Must be zero—This field must be zero.
• AFI—Address Family Identifier, 2 for IP.
• IP Address—Destination IP address of the route. It can be a natural network, subnet or a host
address.
• Metric—Cost of the route.
RIPv2 message format
The format of RIPv2 message is similar to RIPv1.
Figure 7 RIPv2 Message Format
Differences from RIPv1:
Command
AFI
IP address
Version Unused
Subnet mask
Next hop
Route tag
Metric
0 7 15 31
Route
Entries
Header