A fault-tolerant protocol for location directory maintenance in mobile networks

In this paper, we present a fault-tolerant protocol for maintaining location directories in mobile networks. The protocol tolerates base station failures and also allows for consistent location information to be maintained about mobile hosts that switch off and arbitrarily reappear in some other part of the network. Further, the protocol tolerates the corruption of a logical time stamp that is part of any protocol where new location information has to be distinguished from old location information when a location directory is updated. We formally show that the protocol maintains consistent location information and does not overwrite new location information with old location information. The protocol can be hierarchically organized to reduce the message overhead incurred by location directory updates.<>