A novel incrementally-deployable multi-granularity multihoming framework for the future internet

Multihoming practice in the current Internet is limited to hosts and autonomous systems (ASs). It is 'connectivity-oriented' without support for user or data multihoming. However, the swift migration of Internet from 'connectivity-oriented' to 'content-oriented' pattern urges to incorporate user and data level multihoming support in architecture designs instead of just through ad-hoc patches. In this paper, based on our previous research experience, we expand the multihoming concepts to both user and data levels based on the 'multiple points of attachment' in a way similar to host multihoming. We propose a new incrementally-deployable multihoming framework by introducing a 'realm' concept. The high-level user and data multihoming support can be built on top of the host and AS level multihoming in an incrementally-deployable and flexibly-assembled manner. Realms form a hierarchy of functionally dependable blocks. We define a new dimension of building block - slice which is an incrementally implementable functional unit for multihoming. Besides the long-term support for user and data multihoming, the first step deployment of the new framework is also able to address the short-term routing scalability challenge by reducing the total inter-domain routing table size gradually.