In order to ease the development and maintenance of more complex P2P applications, which combine multiple P2P functionality (e.g. streaming and dependable storage), we suggest to extend structured P2P systems with a dedicated information management layer. This layer is meant to generate statistics on the whole P2P system and to enable capacity-based peer search, which helps the individual functionality layers in the P2P application to find suitable peers for layer-specific role assignment. We present in this paper SkyEye.KOM, an information management layer applicable on DHTs, which fulfills these desired functionality. SkyEye.KOM builds an over-overlay, which is scalable by leveraging the underlying DHT, easy to deploy as simple add-on to existing DHTs and efficient as it needs O(log N) hops per query and to place peer-specific information network wide accessible. Evaluation shows that SkyEye.KOM has a good query performance and that the costs for maintaining the over-overlay are very low.

1. SkyEye.KOM: An Information Management Over-Overlay for Getting the Oracle View on Structured P2P Systems Kalman Graffi , Aleksandra Kovacevic, Song Xiao and Ralf Steinmetz Underlay: The Internet Structured Overlay: DHT Information Management Over-Overlay Pick good peers ? Does my p2p system work?

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