Research On Key Problems In Mobile IP Networks

As the development of Internet and the wide use of mobile computers, the users of mobile computers are expecting to get access to Internet freely and to share public resources with others like desk-top users. The IETF has developed a protocol according to the requirement of mobile computer users, named Mobile IP. Mobile IP achieves the perfect combination of IP technology and mobile communication technology, which makes the big change in terms of data communications. It would make the dream come true that anyone could communicate with others through any access methods at anytime anywhere.Mobile IP has been developed dramatically. However, there are still some problems in Mobile IP. This thesis analyzes three problems in Mobile IP and proposes the solutions to them.First, the transmission of mobile IPv6 is based on best-effort, so it cannot provide any QoS guarantee for real-time business. Mobile IP should be combined with Resource Reservation Protocol (RSVP) in order to guarantee the QoS of multi-media services. However, RSVP, which is designed for the fixed networks, becomes invalid in wireless mobile environment. Therefore, some RSVP extensions have been proposed, one of which is DRSVP. It has become more meaningful to use DRSVP to support mobile IP technology. In this thesis, Dynamic RSVP (DRSVP) is extended to support soft handoff in wireless mobile IP networks to provide QoS guarantee for real-time services.Second, Mobile IP aims at providing mobility support at network layer, and only supports terminal mobility and mode mobility. The main characteristic of future network is that a mobile user can get access to heterogeneous networks through a set of devices and handoff between different service providers smoothly. Therefore, several new kinds of mobility need to be considered in the future wireless communications technologies, such as personal mobility, session mobility and service mobility. Therefore, Mobile IP should be integrated with the application layer protocol, Session Initiation Protocol (SIP), to support all kinds of mobility with the optimal performance. In this thesis, a new two-layer mobility management architecture integrating both Mobile IP and SIP...