Programmable Port Forwarding for Mobile Peers in Private Networks

Peer-to-Peer file sharing networks have gained tremendous popularity in recent years. However, traversing Network Address and Port Translators (NAPT) may still fail in certain topologies. In this paper, we present Programmable Port Forwarding, a lightweight approach for allowing private hosts to fully participate in a Peer-to-Peer network. By extending the NAPT that a private host uses to connect to hosts outside its private realm, we enlarge the applicability of Peer-to-Peer systems in today’s networks. Additionally, we show that our proposed solution is able to deal with terminal mobility within the domain of the NAPT server as well.