RIPng packets are sent using the UDP protocol and the protocol port number 521. Unsolicited updates messages are sent with 521 as both the source and destination port.
Source IP address
The Link-Local IPv6 address of the interface sending the RIPng packet is used as the source IP address of any RIPng update sent.
Destination IP address
The destination IP for any periodic or triggered update should be sent to the multicast group FF02::9, (all-rip-routers multicast group). When sending responses to an RIPng request, the RIPng response is sent to the unicast IP address of the requester.
Each route entry in an update message contains the following:
IPv6 prefix
prefix length
route metric
route tag (optional)