Anycasting-based protocol for geocast service in mobile ad hoc networks

Geocasting is a variation on the notion of multicasting. Geocasting is useful for sending messages to nodes in a specified geographical region. This region is called the geocast region. This paper presents a protocol, named GeoTORA, for geocasting in mobile ad hoc networks. The proposed GeoTORA protocol combines anycasting with local flooding to implement geocasting. Thus, GeoTORA requires two phases for geocasting. First, it performs anycasting from a source to any node in the geocast region, by modifying the Temporally-Ordered Routing Algorithm (TORA) (unicast) routing protocol. Subsequently, localized flooding within the geocast region is performed to deliver the messages to nodes within the geocast region. This integration of TORA and local flooding can significantly reduce the overhead of geocast delivery, while maintaining reasonably high accuracy. 2002 Elsevier Science B.V. All rights reserved.