Q.
Why Vigor Router can not get routing information via RIP
from other routers ?
RIP protocol has two versions: RIP v1 and RIP v2.
RIP v2 consists of RIP-2B and RIP-2M. Both RIP-2B and RIP-2M
send the routing data in RIP-2 format; the difference being
that RIP-2B uses subnet broadcasting while RIP-2M uses multicasting.
Multicasting can reduce the load on non-router machines
since they generally do not listen to the RIP multicast
address and so will not receive the RIP packets.
Note: Vigor Router just support RIP-2M.
So if a router sends RIP information using RIPv1 or RIP-2B,
Vigor Router will not accept it.
Below is a log captured on the LAN side of Vigor2910. The
address 224.0.0.9 is a multicast address, 192.168.4.255
is a broadcast address. Vigor2910 will just accept the RIPv2
information with destination 224.0.0.9.
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