Availability analysis of an ad-hoc DSMS for disaster relief environments

The number of victims rescued alive when a disaster occurs depends on the efficiency of search and rescue teams. Hence, communication, coordination and collaboration must be developed as best as possible. Currently the communication infrastructure, radio gear, permits us only to transfer audio signals, so enhancing group interaction by providing complementary communication media and services is a challenge. An ad-hoc network formed by wearable devices operating in a peer to peer architecture with limited wireless coverage seems appropriate for this need. We have designed an ad-hoc distributed shared memory system, focused on issues generated by peer mobility, to provide a transparent way for applications to interact. Also, we developed a simulation model to analyze the amount of replication needed to obtain a reliable medium. A trade-off appeared between the transparency provided to the applications and the system´s availability. The results suggest that it is possible to build a reliable communication system.