基于马尔可夫链的移动IP注册时间建模与优化

Modeling and Optimization of Mobile IP Registration Time Based on Markov Chain

在大规模移动IP网络中,移动节点的注册请求消息在代理节点处容易产生冲突,导致移动节点在不同链路间的切换时延较大。针对该问题,提出一种以当前需要注册的节点数为变量的一维马尔科夫链模型,在此模型的基础上通过公式推导得出链路中所有移动节点完成注册的总时间和竞争窗口值的关系式,移动节点可以根据当前需要注册的节点数调整自身的竞争窗口值,从而避免节点间的冲突,使得注册总时间最小。在Glo Mo Sim仿真环境中实现移动IP协议,并通过仿真结果和理论结果的比较验证了该模型在确定最优竞争窗口值时的有效性。

In large scale mobile IP networks,the registration request from the mobile nodes collides at the agent node,and results large handoff delay. To solve this problem,a one-dimensional Markov chain model is proposed,which takes the mobile nodes needing to register into consideration. On the basis of the model,the relationship betw een the total time for all the mobile nodes finishing their registration and the value of their contention window is derived. Mobile nodes can adjust the value of their contention window to avoid collisions,thus achieve better registration time performance.Afterw ards,the mobile IP protocol is implemented in GloMoSim. The effectiveness of the model in optimizing the value of the contention window is validated by comparing the simulation results with the theoretical results.