Path expiration times in mobile ad hoc networks

Mobile ad hoc networks are infrastructure free, dynamic and wireless networks. Nodes within a network are able to create connections over several intermediate relays to distant nodes. Nodes establish connections by setting up determined paths through the network. The path expiration time (PET) is the path lifetime and unpredictable node movements limit it. Whenever adjacent nodes, used as connection relays, leave each others radio range they cause a failure within the path. The source must then reestablish the connection using another path, which avoids the broken link. We describe a statistical method to forecast PETs over an arbitrary number of hops, independent from radio transmission ranges, maximum node velocities and external sensor data. This probability distributions can be exploited for dimensioning ad hoc networks, therewith they comply certain requirements of path stability, e.g. by limiting the maximum number of hops over which a path can be set up.