Adopting IPsec to SIP Network for On-Demand VPN Establishment between Home Networks

We have developed a new on-demand VPN system that works over a managed SIP network such as the next-generation network (NGN). The system achieves a stable broadband VPN connection between two home networks in an easy-to-use manner by using SIP for session management. The system uses telephone numbers, QoS management, and packet-filtering capabilities that are provided by the NGN. In this paper, we describe the system and focus on how IKEv2 and IPsec, with a slight extension to the port-number handling, can be adapted to an NGN that has NAT- or 5-tuple-based packet filtering within the network.