Research On IP Mobility In Mobile Computing Networking

The concurrent and deployment of the Internet and mobile communication led to a new environment known as mobile or nomadic computing. The emergence of wireless mobile computing, especially the mobility of computers, introduces challenging new problems that were encountered in design and implementation future mobile networks. Due to the heterogeneous future wireless mobile networks, this will demand pervasive IP mobility support when a mobile host roams around. However, the current TCP/IP protocol suite is not able to fully support IP mobility, especially where real-time applications are concerned.This dissertation investigates the above stated mobility problem impact on the design and implementation of network (IP) and transport layer protocols (TCP). The major achievements are outlined as follows.1. We analyze several Mobile IP proposals and describes the implementation of IETF Mobile Internet Protocol(IP) with the Linux and presents results of some experiments that quantify the effects of overheads introduced by Mobile IP on the transmission of Transmission Control Protocol segments.2. We study the costs of the Mobile IP and Mobile IP with Route Optimization handoff that occurs when a mobile host moves between All-IP cells. Experiments were carried out with Mobile IP and TCP over varying network conditions to observe the effect of handoffs on the transmission. The results show that although Mobile IP may be appropriate for macro mobility applications, its long handoff periods make it unsuitable for micro mobility support.3. A new method of hierarchical mobility management (LTMIP) is presented, which introduces buffer management and Link triggering mechanism .Simulation results show substantial performance improvements in terms of throughput, registration overhead, loss and duplicate packets during a handoff.4. We also propose another mobility management scheme (MFMIP) to overcome the ping-pang effect when Mobile host mobile access Internet in the future wireless overlay network, where a number of networks offer similar coverage and bandwidth on the same overlay level.5. A novel transmission control protocol, FRL-TCP is proposed, which eliminates some transport-layer functions and simplifies other functions, leads to reducedcommunication load on the wireless link. The new protocol takes advantage of link layer explicit notification and retransmissions to quickly recover losses over the wireless link. Simulation results show a substantial performance improvement achieved. 6. Based on IPv6, a new architecture for mobile computers is proposed. The concept of the mobile Internet is introduced. The proposed scheme, which differentiates global mobility management from local mobility management dynamically, differentiates idle host from active host, significantly reduces the signaling load and power consuming.