A novel adaptive method for minimizing recurrent handoff delays in Mobile IPv6 networks

Future wireless networks will be entirely based on the IP protocol. High degrees of portability available in an all-IP network will be possible only if we are able to address the insufficiencies of mobility management. One of the major insufficiencies affecting mobility management is the delay associated with the handoff process. During a handoff, the mobile node can become unreachable causing data destined to the node to be lost. As a result, it is important to minimize the delays associated with the handoff process. In this research, we evaluate various mobility management protocols and show that Mobile IPv6 is the most appropriate solution for micro-mobility management. We study the handoff process using Mobile IPv6 and characterize its phases. This characterization shows that move-detection delay is the bottleneck of the handoff process accounting for almost 60% of the combined Layer-2 and Layer-3 handoff delays. To minimize this delay, the router advertisement interval should be set as short as possible without exceeding its assigned bandwidth. This approach has been studied in previous work but only in the context of a single handoff. We propose an improved mobility analysis that assumes a more realistic model that incorporates recurrent handoffs likely to occur during Eager Cell Switching. We then derive an expression for bandwidth that accounts for the non-zero delay separating consecutive handoffs. Further, we use our analysis to provide a new adaptive mobility method capable of dynamically adjusting the advertisement interval as a function of the recurrent cell switching behavior and the available bandwidth. Finally, we verify this model using analysis and simulations using OPNET® and MATLAB® based simulators. Results show the reduction in move detection delay to be as much as 65% using the analysis and as much as 56% using simulation.Applied Science, Faculty ofElectrical and Computer Engineering, Department ofGraduat