Formal Approach for Resilient Reachability based on End-System Route Agility

The deterministic nature of existing routing protocols has resulted into an ossified Internet with static and predictable network routes. This gives persistent attackers (e.g. eavesdroppers and DDoS attackers) plenty of time to study the network and identify the vulnerable (critical) links to plan devastating and stealthy attacks. Recently, Moving Target Defense (MTD) based approaches have been proposed to to defend against DoS attacks. However, MTD based approaches for route mutation are oriented towards re-configuring the parameters in Local Area Networks (LANs), and do not provide any protection against infrastructure level attacks, which inherently limits their use for mission critical services over the Internet infrastructure. To cope with these issues, we extend the current routing architecture to consider end-hosts as routing elements, and present a formal method based agile defense mechanism to embed resiliency in the existing cyber infrastructure. The major contributions of this paper include: (1) formalization of efficient and resilient End to End (E2E) reachability problem as a constraint satisfaction problem, which identifies the potential end-hosts to reach a destination while satisfying resilience and QoS constraints, (2) design and implementation of a novel decentralized End Point Route Mutation (EPRM) protocol, and (3) design and implementation of planning algorithm to minimize the overlap between multiple flows, for the sake of maximizing the agility in the system. Our PlanetLab based implementation and evaluation validates the correctness, effectiveness and scalability of the proposed approach.