The demand for faster failure-recovery in pure intra-domain IP networks has led to the development of several IP Fast ReRoute (IPFRR) mechanisms. However, these mechanisms are all either too computationally expensive, or fail to provide satisfiable protection coverage. For these reasons, IPFRR schemes have yet to see widespread commercial deployment. In this paper, we present a new IPFRR mechanism called Tunnel-AT based on incremental SPF algorithm and the concept of Attaching Tree. Tunnel-AT outperforms existing IPFRR mechanisms by providing 100% node protection coverage at a computational cost of less than one full SPF calculation.

Internet routing tables have been growing rapidly due to factors such as edge-site multihoming, traffic engineering, and disjoint address allocations. To address the routing scalability problems caused by this rapid growth, we propose an evolutionary approach that is incrementally deployable and provides immediate benefits to any adopting ASes. The basic premise of the approach is that route aggregation removes from routing tables the unnecessary topological details about remote portions of the Internet. We demonstrate that aggregation can be applied incrementally starting from local scopes within individual routers and individual ASes, and gradually expanded to the global Internet scope. The evaluation studies show that route aggregation is effective in addressing FIB scalability problems within a router and within a network.