Ivan Dedinski Alexander Hofmann Bernhard Sick Cooperative Keep-Alives: An Efficient Outage Detection Algorithm for P2P Overlay Networks. 140-150 2007 Peer-to-Peer Computing http://doi.ieeecomputersociety.org/10.1109/P2P.2007.15 conf/p2p/2007 db/conf/p2p/p2p2007.html#DedinskiHS07