3Com MSR 50 Series Configuration Manual page 974

974 C 59: RIP C
HAPTER ONFIGURATION
Figure 295 RIP-1 Message Format
0
Command
Header
Route
Entries
Command: The type of message. 1 indicates Request, 2 indicates Response.
■
Version: The version of RIP, 0x01 for RIP-1.
■
AFI: Address Family Identifier, 2 for IP.
■
IP Address: Destination IP address of the route; can be a natural network,
■
subnet or a host address.
Metric: Cost of the route.
■
RIP-2 message format
The format of RIP-2 message is similar with RIP-1.
Figure 296 RIP-2 Message Format
0
Command
Header
Route
Entries
The differences from RIP-1 are stated as following.
Version: Version of RIP. For RIP-2 the value is 0x02.
■
Route Tag: Route Tag.
■
IP Address: Destination IP address. It could be a natural network address,
■
subnet address or host address.
Subnet Mask: Mask of the destination address.
■
Next Hop: If set to 0.0.0.0, it indicates that the originator of the route is the
■
best next hop; Otherwise it indicates a next hop better that the originator of
the route.
RIP-2 authentication
RIP-2 sets the AFI field of the first route entry to 0xFFFF to identify authentication
information. See Figure
7 15
Version
AFI
IP address
Must be zero
Must be zero
Metric
7 15
Version
AFI
IP address
Subnet mask
Next hop
Metric
297.
Must be zero
Must be zero
Figure 296 shows it.
Unused
Route tag
31
31