1 HAIR: Hierarchical Architecture for Internet Routing

Super-linear routing table growth, high update churn, lack of mobility and security, insufficient support for multi-homing and traffic engineering are some of the significant deficien-cies of today’s Internet. More and more researchers are convinced that these shortcomings cannot be resolved by incremental and band-aid solutions. In this paper, we introduce HAIR, a scalable routing ar-chitecture for the future Internet. It addresses many of the problems the Internet is facing today. The focus is on limiting routing table size and update churn while supporting legacy hosts and avoiding unnecessary burden for transit providers. The key idea is to combine a hierarchical routing approach with locator/identifier separation: The routing as well as the mapping system are organized in a hierarchical manner where updates to both systems are not globally visible as far as possible. First experiences with a prototype implementation are promising and demonstrate a potential migration path where legacy devices are supported as well. 1