Main Article Content
Recently, peer-to-peer (P2P) systems generate a large amount of unwanted cross-domain traffic on the Internet due to a lack of knowledge about physical network topology. The unwanted cross-domain traffic is especially costly for the internet service providers (ISPs). To reduce the cross-ISP/AS (autonomous system) traffic, the existing approaches introduce network-aware strategies in which a lot of modifications of P2P systems are required. In particular, each P2P application must be modified to integrate with a locality-aware procedure and/or a communication protocol to obtain the topological information from an ``oracle" server. In this paper, we propose two schemes for localizing P2P traffic without any peer reaction: (1) fixed-length bandwidth limitation scheme, (2) hierarchical bandwidth limitation scheme. By intentionally limiting the bandwidth of each connection path between peers based on geographical location of the peersâ€™ destinations, the traffic can be localized with single level for the first scheme and with multiple levels for the second scheme. Compared to the existing locality-enhancing approaches, our two schemes require neither dedicated servers, nor cooperation between ISPs and users, nor any modification of existing P2P application software. Therefore, we believe that all types of P2P applications can easily utilize our proposals. Experiments on P2P streaming applications indicate that the fixed-length bandwidth limitation scheme successfully realizes P2P traffic localization. Moreover, the hierarchical bandwidth limitation scheme not only significantly reduces the cross AS/ISP traffic but also maintains a good performance of P2P applications.