Resilient and underlay-aware P2P live-streaming
Application Layer Multicast (ALM) represents a cost-efficient way to disseminate content in large scale. However, as it relies on end-systems in content distribution, it can be easily attacked and thus requires specific measures to increase its resilience against attacks. Besides attacks on end-users, few attention has been paid to attacks on the underlying transport network so far. When the overlay is not constructed in an underlay-aware manner, several overlay links may rely on the same link or router in the underlay. Hence, a single underlay failure may result in multiple, simultaneous overlay failures. Moreover, without considering the underlying transport network an inefficient content distribution can be the result. For this reason the ALM induced traffic load in transport networks can become rather large. In this article, we propose a construction algorithm for ALM topologies that incorporates information about the underlying network to improve their resilience against underlay failures, to maintain resilience against overlay attacks, and to increase the efficiency of the content distribution. Our simulation results indicate that the underlay dependence of the established ALM overlays can be nearly halved compared to overlays that do not use information about the transport network in their construction. As a result, the ALM induced traffic load in transport networks decreases considerably. In addition, the results indicate that our topologies are likewise resilient to underlay as well as overlay attacks.