Traffic Locality in the eMule System

Traffic locality is a promising way for P2P systems to reduce cross-network traffic and improve performance. For the specific application, eMule, there are few reports on traffic locality in eMule to date. In this paper, we study how to integrate traffic locality mechanism into the eMule system. The eMule protocol is summarized and the source code of the eMule software is analyzed. Then traffic locality mechanisms for eMule are proposed. The methods are based on measurement with ICMP ping packet to get hop distance and RTT between peers. Then a peer chooses peers with shorter hop distance or RTT as sources to connect to and to request for downloading. Simulation experiments show that such simple mechanisms can cut-down cross-network traffic greatly and ameliorate download performance of the eMule system explicitly at the same time.