SSVHOP: A Simple and Seamless Vertical Handoff Protocol for Loosely Coupled Integrated UMTS/WLAN Network

摘要

To provide anywhere at any time services in an integrated wireless networking environment, seamless mobility is one of the most important and challenging issues. Recent literature shows that the seamless mobility can be achieved by performing significant modifications in existing network designs and protocol architectures. However, such intensive modification increases the network implementation complexity and deployment cost. In this study , we have proposed a Simple and Seamless Vertical Handoff Protocol (SSVHOP) to attain the seamless mobility without implementing any major modification in the existing network topology or protocol architecture. The foundations of the underlying principle of the SSVHOP are based on a proactive RSS handoff triggering mechanism and multi-homing capabilities of mobile terminal. In addition, SSVHOP reduces the signaling and processing cost of the network to achieve low handoff delay and packet loss during upward and downward vertical handoff scenarios. Moreover, it has been observed that the proposed design also improves the data session performance by routing the data packets on the optimal route and by introducing an overhead free mechanism for data transportation in an integrated UMTS/WLAN network. We evaluated and compared the SSVHOP with the tight coupling mechanism. By analyzing mathematical modeling and simulation results, it is evident that the SSVHOP performs better than the tight coupling mechanism for all tested applications and measurement parameters.