An efficient resource reservation scheme based on gray-cell in wireless mobile networks

In order to provide continuous QoS guarantees to a mobile user, it is required to deploy a mechanism which reserves resources in advance at the locations to which the mobile user is expected to move. An important issue with regards to these mechanisms is to minimize the waste of resources caused by redundant reservations while keeping up the QoS services to the user. In this paper, we propose a wireless network domain structure which deploys a special cell, called a gray cell. The boundaries of wireless network regions are surrounded by the gray cells, and the gray cells are supposed to belong to all of their neighboring regions. Based on this structure, we propose a mechanism which completely removes the waste of redundant resource reservation while greatly reducing the risk of reservation disruption caused by inter-region handovers. Using simulation, it is shown that the proposed mechanism can deal with inter-region handover as effectively as it does with intra-region handover. It is also presented that the proposed mechanism outperforms existing mechanisms with respect to reservation disruption time and packet losses caused by handovers.