A Fast Handover Scheme Based on Smart Triggers and SIP

All-IP mobile networks require a mechanism for enabling seamless handovers between different access technologies. For real-time services, such as voice and video, the Session Initiation Protocol (SIP) is becoming the leading signalling protocol in IP networks and has already been accepted as the signalling standard in 3G wireless systems. However, existing proposals for supporting mobility with SIP suffer from undesirable delay in multimedia applications. The IEEE 802.21 Media Independent Handover (MIH) group has proposed a new layer called layer 2.5 (L2.5) or MIH layer that offers advanced services for handover such as event notification, L2 handover commands and information on available networks. In this paper, we combine the 802.21 MIH smart triggers with SIP mechanism to provide a fast handover solution. We also modelled this combination using OPNET network simulation tools and show how the event triggers could improve the handover initiation time.