ABSTRAKSI: Teknik IP multicasting dapat dipergunakan untuk menutupi kelemahan utama yang dihadapi pada sistem Peer-to-Peer (P2P) terutama berkaitan dengan resource client dan juga jaringan. Dengan IP multicasting trafik sistem akan direduksi karena user hanya perlu mengirimkan satu copy packet/datagram yang oleh multicast router akan digandakan dan didistribusikan ke jaringan melalui multicast tree. Pada Tugas Akhir ini dibahas mengenai penerapan teknik IP multicasting pada sistem P2P melalui simulasi dengan contoh aplikasi video conference disertai asumsi dan pendekatan sesuai ketetapan yang berlaku. Dengan memperbandingkan performansi jaringan dari berbagai protokol routing akhirnya akan didapatkan protokol routing apa yang paling sesuai untuk diterapkan pada sistem P2P.Kata Kunci : P2P, multicast, protokol routing, intra-domain, inter-domain, throughput, end-to-end delay, packet loss.ABSTRACT: IP multicasting technique could be used to covered the weaknesses of P2P system especially related to clients and network resources. With IP multicasting technique, system traffic would be reduced because user only have to send one copy of packet/datagram. Multicast router make copies of incoming data and distribute them to a multicast tree. In this Final Task, implementation of IP multicasting over P2P systems has been done by simulating application such as videoconference system along with the assumptions and approaches according to recently standardizations. Finally, we will have the most suitable routing protocol which could be implemented on P2P systems.Keyword: P2P, multicast, routing protocol, intra-domain, inter-domain, throughput, end-to-end delay, packet loss.