Voronoi diagram and convex hull based geocasting and routing in wireless networks

• Authors: Ivan Stojmenovic;Anand Prakash Ruhil;D. K. Lobiyal
• Venue: ISCC '03 Proceedings of the Eighth IEEE International Symposium on Computers and Communications
• Year: 2003

A broad variety of location dependent services willbecome feasible in the near future due to the use of theGlobal Position System (GPS), which provides locationinformation (latitude, longitude and possibly height) andglobal timing to mobile users. Routing is a problem ofsending a message from a source to a destination.Geocasting is the problem of sending a message to allnodes located within a region (e.g. circle or square).Recently, several localized GPS based routing andgeocasting protocols for a mobile ad hoc network werereported in literature. In directional (DIR) routing andgeocasting methods, node A (the source or intermediatenode) transmits a message m to all neighbors locatedbetween the two tangents from A to the region that couldcontain the destination. It was shown that memorylessdirectional methods may create loops in routing process.In two other proposed methods (proven to be loop-free),geographic distance (GEDIR) or most forward progresswithin radius (MFR) routing, node A forwards themessage to its neighbor who is closest to destination, orhas greatest progress toward destination (respectively).In this paper, we propose a general algorithm (based onan unified framework for both routing and geocastingproblems), in which message is forwarded to exactlythose neighbors which may be best choices for a possibleposition of destination (using the appropriate criterion).We then propose and discuss new V-GEDIR and CH-MFRmethods and define R-DIR, modified version ofexisting directional methods. In V-GEDIR method, theseneighbors are determined by intersecting the Voronoidiagram of neighbors with the circle (or rectangle) ofpossible positions of destination, while the portion of theconvex hull of neighboring nodes is analogously used inthe CH-MFR method. Routing and geocasting algorithmsdiffer only inside the circle/rectangle. We proposememoryless and past traffic memorization variants ofeach scheme. The proposed methods may be also used forthe destination search phase allowing the application ofdifferent routing schemes after the exact position ofdestination is discovered. Memoryless V-GEDIR and CH-MFRalgorithms are loop free, and have smaller floodingrate (with similar success rate) compared to directionalmethod. Simulations, involving the proposed and someknown algorithms, are in progress and confirm ourexpectations.