A session relay apparatus for preventing the packet relay delay by detecting the start and end of the policy settable peer-to-peer communication is disclosed. The session relay apparatus for relay a session control message transmitted and received between communication terminals to control the peer-to-peer...http://www.google.com.hk/patents/US7522591?utm_source=gb-gplus-share專利 US7522591 - Policy settable peer-to-peer session apparatus
