Location-based services: A framework for an architecture design

Location awareness describes applications in computing and telecommunications, which alter their behaviour in dependence on the location of an entity, such as the user of an application, a person the user of the application wants to communicate with, or an object capable of changing a location. Such location presents a major category of context and it is derived by various methods of positioning. Over the past two decades, positioning has been a driving factor in the development of ubiquitous computing applications demanding such location information. Many devices and techniques have been developed; however, very few of them are actually used commercially. This is because the precision is limited to specific applications, and the availability limited to the provider of specific services. Obviously, to support efficient and effective development and deployment of innovative Location–Based Services (LBSs), namely, services able to deliver personalized location-aware content to subscribers on the basis of their positioning capability of the wireless infrastructure, a flexible middleware should be build as the enabling infrastructure. This work examines various systems of LBSs focusing on their architecture characteristics and the different governing platforms and technologies on which they are based. The goal is to contribute towards the development of an architecture that combines numerous individual positioning technologies to obtain more precise and more reliable results according to the various needs of the whole range of LBSs. The general concepts of these systems are discussed by presenting a first level of classification which depends on the positioning infrastructure namely, indoor, satellite or network-based configuration. Several specific LBS architectures are categorized by means of the various characteristics regarding the design and functionality of each one. Position is combined with spatial information so as to integrate a system of LBSs with Geographical Information Systems (GIS) or other location dependent information. Finally, to increase interoperability among the various systems and technologies, standardization and homogenization is also taken under consideration.