Recently, mobile SCTP (mSCTP) has been proposed as a transport layer approach for supporting mobility. mSCTP is based on the 'multi-homing' feature of Stream Control Transmission Protocol (SCTP), and utilizes the functions to dynamically add or delete IP addresses of end points to or from the existing connection in order to support mobility. In this paper, we propose a transport layer mobility supporting scheme, which is based on mSCTP and utilizes the link layer signal strength information in order to determine when to add or delete end-point IP addresses of mobile node and how to change data delivery paths when handover happens. Exploiting the fact that the transport layer is aware of the mobility in the proposed scheme, we also propose error and congestion control enhancement to cope with handover efficiently. The simulation results show that the performance of proposed scheme is competitive compared to the traditional network layer mobility supporting approach. Especially, when the moving speed of mobile node is fast or new path acquisition takes long, it shows better performance than the traditional network layer approach.

Next generation wired/wireless networks will be based on IP technology. In the IP based networks, it is crucially required to support seamless mobility especially for proving real-time services in the mobile environment. The conventional Mobile IP protocols cannot satisfy such seamless mobility requirements for real-time services. Therefore various extensions of Mobile IP are being proposed. In this paper, we propose a new handover scheme to enhance the existing tunnel-based fast handover method, which is a typical Mobile IP extension to support seamless mobility. It is shown that the proposed method reduces the traffic overhead in the networks. It is expected that the proposed method will be particularly useful in the IP-based networks in which there are a number of users simultaneously using the long-lived real-time services, or in the condition that the traffic overhead is considered as a critical performance measure.