The "Le" interface: performance evaluation of 2-tier and 3-tier 3GPP compliant realizations

Location-based services (LBS) constitute one of the most attractive services' categories for cellular networks. 3GPP defines the "Le" interface for external LBS provision and access to the core network of mobile operators. Multiple proprietary and commercial protocols and APIs can be used to implement this interface. The paper examines the realization of "Le" interface according to the proposed 3GPP standards, namely the mobile location protocol (MLP) over HTTP and the mobility API of OSA/Parlay using middleware technologies. The performance of both approaches is evaluated. Furthermore, with respect to the mobility API of OSA/Parlay, three implementations, based on respective middleware technologies (CORBA, RMI and Web Services over SOAP), are examined, for evaluating the performance of each OSA/Parlay gateway. The results of the experiments provide useful performance indicators concerning the efficiency of the internal architecture of each implementation as well as the anticipated speed of the user-service interaction.