More than half of Internet traffic today is contributed by peer-to-peer (P2P) systems. P2P systems build their overlay topology largely agnostic of the Internet underlay, which often leads to traffic management challenges for Internet Service Providers (ISP) and potentially inefficient neighborhood selection for P2P nodes. To overcome this, we propose to use an oracle hosted by the ISPs, so that ISPs and P2P users can cooperate for improved performance. The oracle can be queried by P2P nodes while choosing neighbors for content search, and it will rank the possible neighbors of the querying node according to a locality indication, like the AS-hop distance. The ISP would gain by keeping traffic within its Autonomous System (AS) network, and the P2P node would experience improved performance like lesser delay and better bandwidth.In this paper, we evaluate the benefits of our scheme by performing experiments in a real Testlab consisting of routers, switches and computers running actual instances of P2P applications. We showhow we configure representative AS topologies for P2P networks using VLANs and trunking ports, andpresent experimental results with content search phase of a P2P network using different file sharing and search query distributions.