Aqua: An Adaptive QUery-Aware Location Updating Scheme for Mobile Objects

Abstract

Conventionally, the problem of location updates for moving objects has been addressed by adjusting the location reporting frequency or setting the uncertainty bound, according to object mobility patterns. This induces an obvious tradeoff between the communication cost and the uncertainty bound in querying moving object locations. Most existing works are focused on the object mobility pattern, without exploring the interdependency between queries and location updates. Furthermore, they take the precision of query results for granted as a result of a negotiated deviation threshold for reporting. The Aqua (Adaptive QUery-Aware) location updating scheme proposed in this paper exploits the interdependency between queries and updates. In particular, our scheme is adaptive to changes in both object mobility patterns and query characteristics, thereby resulting in significant performance improvement in terms of communication cost and query processing precision. We performed simulation studies and demonstrated that Aqua can produce desirable performance in most situations.