Trigger Mechanism of Context Transfers in Seamless Handovers for Multimedia Applications

RSVP faces challenges from resource-engross and switching or thrashing when in handover process, especially when in group mobility and for multimedia applications. This paper proposed a scheme on seamless handover, developed a context transfer mechanism that can keep access routers and home agent informed of handover, AAA and QoS messages before anticipated handover. And a simplification to the HO sequencing with AAA process was made. The context transfer triggered by positioning information approaching cell edge. Constraint condition of mobile node's path probability is introduced from traffic management system to enhance path predicting precision of high-speed mobile nodes. Path attaching is introduced to deduce the whole overhead. Simulation showed that the scheme lessens resource possession, enhances QoS and smoothes handover procedure. The simulation data also showed that time setforward of context transfer is critical to the performance.