Distributed Location Management Strategy Based On Human Mobility

In recent years,with the rapid growth of the number of intelligent terminals,the scale of data traffic in the network grows explosively.However,the current centralized mobility management solution brings several limitations such as suboptimal routing,scalability problems,reliability and single point of failure.Distributed mobility management strategy has become one of the research focuses with the aim of overcoming limitations of centralized solution.In distributed solutions,people pay more attention on how to distribute and deploy the functions of original centralized nodes to reduce the pressure of core network and enhance network scalability.How to divide location area and design a location management strategy based on characteristics of human mobility so as to ensure that the location management strategy is optimal for each user and reduce the overhead of location management strategy is another research focus in distributed mobility management.Based on the above background and existing problems,after investigating the research status of characteristics of human mobility and location management strategies,the main works of this paper include the following two parts:(1)Analysing temporal and spatial characteristics of human mobility from the perspective of individual level by using reality dataset collected by GeoLife project of Microsoft Asia Research Institute.By using time-based passing point extraction and threshold-based stay point extraction,user's GPS positions are converted into stay points and passing points.In order to extract the most frequently visited location sequence of users in one day from the massive mobile data,Selec-tive-PrefixSpan,an improved sequence pattern mining algorithm is pro-posed which outforms the existing algorithms in terms of running time and memory usage.(2)Proposing a distributed location management strategy based on human mobility.By using the improved ST-K-Means(Spatial Temporal-K-means)clustering algorithm,tracking areas(TAs)are divided.The improved Selective-PrefixSpan algorithm is used to find the most frequently visited location sequence to construct the TAL(Tracking Area List).And thereby a distributed location management strategy is designed which includes the strategy of distributed deployment,construction of tracking area list and design of location update and paging strategy.Finally,the performance of location management strategy proposed in this paper is verified.