esides the details related to the new address family, there are no significant implications to routing protocol logics. There are a set of more subtle and minor changes, but those are not covered here. We recommend readers interested in routing to study literature specifically focusing on routing. The first IPv6 related change to routing standards in the IETF was to introduce IPv6 into the Routing Information Protocol (RIP), resulting in a new revision called Routing Information Protocol next generation (RIPng) in 1997 [149]. The RIPng is a distance- vector-based routing protocol designed for Autonomous Systems (ASs)' interior routing purposes. More powerful routing protocols have been developed since RIPng for exterior routing purposes and for more efficient interior routing purposes. These include Multi- Protocol Border Gateway Protocol (MP-BGP) (first in 2000, updated in 2007 [150]), Open Shortest Path First version 3 (OSPFv3) (in 2008 [138]) and Intermediate System to Intermediate System (IS-IS) (in 2008 [151]), of which the last two are the routing protocols commonly used for the internal IPv6 route configuration in the 3GPP networks. The MP-BGP is the routing protocol for external (between ASs) communications. The OSPFv3 and the IS-IS differ from the RIPng, and to some extent from the MP-BGP, by not using a distance-vector approach but instead they are link-state routing protocols. The MP-BGP is not quite a distance-vector protocol, as in addition to distance vectors it uses other pieces of information for routing decisions. The distance-vector based routing protocols work by routers sharing their routing tables with neighbors. The distance-vector information gets propagated through a network and eventually all routers have route entries with metric values towards each IPv6 prefix and next hop pointers to their neighboring routers. In the link-state routing protocols, routers share - or flood - information about their reachable neighbors throughout the network to all other routers, and hence each individual