출처 : http://dpnm.postech.ac.kr/mcs/ReferencesPapers & Documents Papers Kundan Singh and Henning Schulzrinne, "Peer-to-Peer Internet Telephony using SIP" David A. Bryan and Bruce B. Lowekamp, "SOSIMPLE: A SIP/SIMPLE Based P2P VoIP and IM System" Salman A.Baset and Henning Schulzrinne, "An Analysis of the Skype Peer-to-Peer Internet Telephony Protocol", Department of Computer Science, Columbia Uni..