A SIP-Based Seamless-Handoff (S-SIP) Scheme for Heterogeneous Mobile Networks

One of the prominent goals of next-generation mobile communication systems is to support seamless roaming of users across heterogeneous wireless access networks. Although SIP has been regarded as an attractive candidate to provide mobility management in B3G/4G networks because of its flexibility and ease of deployment, it still suffers from unacceptably long handoff delays. In this paper, a SIP-based seamless-handoff (S-SIP) scheme is proposed to overcome this problem in inter-domain roaming. Unlike the other SIP-based handoff methods, S-SIP employs a "make-before-break" procedure for seamless handoffs. Moreover, we also propose the appropriate handoff triggering point for this scheme based on location tracking techniques. Simulations results show that the proposed scheme greatly outperform the general SIP-based handoff scheme.