Multi-domain issues of resilience

This paper gives an overview and classification of issues related to resilience in a multi-layer multi-domain network environment. Then the work focuses on the Internet inter-AS context, where the introduction of G/MPLS capabilities for traffic engineering may enhance the way traffic is exchanged today. This paper shows that, in this context, network resilience based on fast re-routing can be achieved, complementing existing inter-domain link protection strategies, by using alternative disjoint multi-domain backup paths through other domains. Furthermore, the paper proposes a specific method to apply MPLS label stacking to make such backup paths scalable to larger clusters of inter-protected domains by means of MPLS transit. This transit can be used as a temporary solution before BGP routes are stable. Finally, the latest standardisation activity on the provision of such multiple path information for BGP is also reviewed.