Signal Reduction and Local Route Optimization of SIP-Based Network Mobility

The movement of an entire mobile network is so-called "Network Mobility". Network mobility can widely apply to public transport, such as WLAN aboard. The IETF has proposed the NEMO basic support protocol to handle the network mobility problem. However, the NEMO basic support protocol results in sub-optimality that may not be tolerated by multimedia streaming services. In this paper, a framework, called SIP-NEMO, extends SIP to support network mobility. The proposed SIP-NEMO achieves route optimization not only when the caller and the callee are in different networks but also when the caller and callee are inside the same mobile network. Moreover, in order to save the bandwidth of wireless links, SIP-NEMO reduces the signaling messages using a URI-list service.