Collaborative handover mechanism for real-time services

Next generation networks intend to offer pervasive and ubiquitous services to the customers wherever they are and whatever the application they are using. To achieve this goal, service continuity across homogenous and heterogeneous networks must be guaranteed. Although Fast Mobile IPv6 overcomes the long handover latency of Mobile IPv6 and makes this delay acceptable for real-time applications, the long initiation handover delay represents a constraint for fast-moving mobiles which don´t have sufficient time to exchange all the FMIPv6 messages before the connection is broken. In this paper we propose an enhanced FMIPv6 protocol using Media Independent Handover services. MIH supplies FMIPv6 with lower layer indications that allow the mobile to make intelligent and optimized handovers. This scheme increases the probability of FMIPv6 predictive mode by reducing the handover initiation delay. Moreover, by using link event indications the mobile will be served until its physical disconnection, and as soon as it connects to the new network, the packets will be forwarded from the new access router without waiting for attachment announcement from FMIPv6. We show through analytic analysis that our scheme reduces handover delay as well as packet loss in both predictive and reactive handovers. In addition, buffer size needed to buffer packets in access routers during the handover is smaller. Finally, the proposed mechanism avoids excessive ping pong events among wireless networks.