RIPng is the equivalent of RIP, but for IPv6 networks. It uses the Bellman-Ford algorithm, ans as RIP, the network diameter is limited to 15 hops. It is described by the IETF RFC 2080, it is a RIP v2 redesign that supports the 128 bit IPv6 addresses. It uses multicast UDP on the well-known group ff02::9 and port 521. Due to the IPsec requirement of IPv6 stacks, RIPng does not have the security features that RIP v2 provides: it has to be handled by the IPv6 security layer (IPsec).