Hidra:A Hierarchical Inter-domain Routing Architecture

The Internet inter-domain routing system is facing serious scalability challenge,which represents super-linear growth of the global routing table and increasingly frequent routing updates.The root cause that contributes to the rapid routing table growth is that number of IP prefix identifying location of autonomous system is uncontrollable;the root reason that leads to increasingly frequent routing updates is the flat inter-domain routing architecture.To address these limitations,this paper proposes a Hierarchical Inter-domain Routing Architecture(Hidra).The basic idea of Hidra is to separate edge networks from the core: relatively stable core networks lie in a high-rank routing layer,and a high-rank inter-domain routing protocol is operated among routers in core networks to maintain reachability to all other core networks;in the relatively queasy edge,a low-rank mapping layer along with a corresponding mapping service is introduced to keep the reachability between the edge and core.Because being separated from unstable edge networks,core networks have the enhanced routing stability.Hidra introduces an inter-domain routing identity RID(Routing Idengity) to identify the location of transit autonomous system,which is only defined by transit autonomous system and its provider autonomous system.As a result,scale of global routing table is observably reduced.