指针推进移动性管理策略中指针链长度的概率

Probability of the Length of the Pointer Chains of Pointers Forwarding Mobility Management Strategy

为了降低移动通信网络中位置跟踪操作的代价 ,指针推进策略被提出 .显然 ,指针链长度的确定对这一策略的有效应用是至为重要的 .已有论文假定移动台在位置区的逗留时间服从指数分布的条件下 ,对指针链的长度进行研究 ,但指数分布的特殊性 ,限制了其研究结果的应用 .本文推广了上述结果 ,研究了移动台在位置区的逗留时间服从一般概率分布的指针推进策略 ,通过构造向量马氏过程 ,利用密度演化方法 ,导出了指针链长度的概率公式 ,这个公式可用于对各种指针推进策略性能的评价 .

Location tracking operations in personal communications services (PCS) network are expensive. A location tracking algorithm called Pointer Forwarding is proposed to reduce the location update cost. Obviously, determining the length of pointers' chain is significant for this scheme to be used efficiently. Hitherto, a useful formula of the length of pointers' chain is proposed on the assumption that the residence time of a mobile has an exponential distribution. However, this assumption restricts the result to be used widely. This paper extends the result enormously. Utilizing the density evolution method of vector Markov processes, we obtain a probability formula of the length of the pointers' chains of Pointer Forwarding scheme, where the residence time of a mobile has a general distribution. The formula is suited for evaluating the performance of a variety of Pointer Forwarding mobility management scheme.