The Routing Information Protocol (RIPng) (ng as next generation, further meaning IPv6 networks) is a distance-vector routing protocol. Current RIPng version 1 uses IPv6 packets to deliver routing information. Basically RIPng is extension of RIPv2 features for support IPv6. The main difference compared to RIPv2 are that RIPng does not support authentication by itself and RIPng has specific route entry element for describing next hop address. In nutshell, RIP next generation is stable, widely supported and easy to configure IPv6 protocol. It's implemented on top of the User Datagram Protocol as its transport protocol. It is assigned the reserved port number 521.