Research And Implementation Of Distributed Mobility Management Handover Optimization Mechanism

With the increasing of mobile devices and mobile traffic, centralized mobility anchor becomes a bottleneck that restricts the performance of mobility management and control. To reduce the pressure of the mobility anchor, distributed mobility management deploys the mobility anchor more close to mobile node. It has become one of the hottest topics that current mobile Internet focuses on. In distributed mobility management, handover latency and signaling cost as well as packets forward path after handover has significant influence on real time services. Handover performance is important for the next generation mobile networks. This paper studies the handover optimization mechanism of distributed mobility management.The paper introduces the research status of mobility management, and analyses that current distributed mobility management suffers from several problems such as long handover latency with large signaling overhead and non-optimal local forwarding path. To solve these problems, this paper proposes a fast handover method with local forwarding path optimization consideration for distributed mobility management. In the method, mobility context of the mobile node is transferred between the mobility anchor before and after handover in advance. When handover occurs, binding update and tunnel set up procedures can be performed simultaneously using the mobility context pre-transferred and cached by the local mobility anchor, so that the handover latency and handover signaling overhead can be reduced. Signaling messages of fast handover are enhanced, in which the mobility anchor that the mobile node currently accessed is identified for temporary forward tunnel establishment, so that fast handover can be realized. In addition, the method can support local forward path optimization if the communication distance decreases after handover. By this means, the communication transmission delay can be optimized without introducing extra tunnel overhead which is unnecessary. The paper test and verify handover latency and signaling cost of the proposed method on NS-3platform.