RIPng packets
RIPng uses request and response packets to exchange routing information as follows:
When RIPng starts or needs to update some route entries, it sends a multicast request packet to neighbors.
When a RIPng neighbor receives the request packet, it sends back a response packet that contains the local routing table. RIPng can also advertise route updates in response packets periodically or advertise a triggered update caused by a route change.
After RIPng receives the response, it checks the validity of the response before adding routes to its routing table, including the following details:
Whether the source IPv6 address is the link-local address.
Whether the port number is correct.
A response packet that fails the check is discarded.