Design and implementation of a copy update mechanism on a mobile information announcement system

The bandwidth problem between a mobile computer and an access point is pointed out, and a copy update mechanism, which can make the best use of the limited bandwidth, is proposed. If the bandwidth of a network is not sufficient, a mobile computer cannot announce all resources, and cannot update some copies on fixed computers. To satisfy client's requests with given bandwidth as much as possible, the proposed mechanism limits traffic of storage type resources in order to announce non-storage type resources prior to storage type resources. Traffic is controlled by limiting the number of concurrent update operations for announcing storage type resources. We implement the prototype and evaluate it. The results show that it can stably announce non-storage type resources.