Predictive Algorithms for Symmetric NAT Traversal Using Port Allocation Functions

Network Address Translators (NAT) introduce significant challenges for peer-to-peer (P2P) communication services, such as Voice-over-IP (VoIP), by necessitating the use of central relay servers. This paper addresses the problem of traversing symmetric NATs, which are particularly problematic due to their complex port allocation rules. We propose several novel algorithms that exploit predictable port allocation functions to establish direct connections between hosts behind symmetric NATs. Our approach models the network environment as a stochastic process and evaluates the proposed algorithms under various network conditions. Simulation results demonstrate that our algorithms achieve high success rates, especially in low-workload networks, while minimizing system resource requirements. The theoretical insights gained from this work contribute to more efficient NAT traversal techniques, improving communication performance in security-sensitive P2P applications. Network Address Translators (NAT) introduce significant challenges for peer-to-peer (P2P) communication services, such as Voice-over-IP (VoIP), by necessitating the use of central relay servers. This paper addresses the problem of traversing symmetric NATs, which are particularly problematic due to their complex port allocation rules. We propose several novel algorithms that exploit predictable port allocation functions to establish direct connections between hosts behind symmetric NATs. Our approach models the network environment as a stochastic process and evaluates the proposed algorithms under various network conditions. Simulation results demonstrate that our algorithms achieve high success rates, especially in low-workload networks, while minimizing system resource requirements. The theoretical insights gained from this work contribute to more efficient NAT traversal techniques, improving communication performance in security-sensitive P2P applications.