Seamless handover between WiMAX and UMTS

The challenge of providing seamless services to the end users moving from one network area to another has become a critical issue for the operators to focus on. Intersystem handover can be a solution whilst to maintain the continuation of an on-going session, IP management is a key issue. Henceforth, to resolve the intersystem handover, both application layer and network layer should be the points of focus for the service providers. But none of the available methods like 3GPP IMS, coupling, MIH and MIP deals with both the network and application layers. IMS mainly manages the multimedia session in the application layer with SIP protocol and MIP works in the network layer with IP protocol. In this paper we propose a method that uses both IMS and MIP simultaneously to resolve the seamless intersystem handover between WiMAX and UMTS to take advantages of these two methods with a result of no packet loss and minimum latency so that the end users can get services without any interruption.