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This paper presents a study of the performance of A-GPS based on OMA SUPL (Secure User Plane Location) in urban areas. Field tests are conducted to compare A-GPS versus conventional GPS using commercial cell phones. Test scenarios include urban indoor and urban outdoor areas. Performance is measured in terms of TTFF (Time To First Fix) location delay and location accuracy. Results for a dedicated handheld GPS receiver are also provided as a reference.

There is an increasing demand of multimedia and location aware services when an accurate and immediate response is needed, for example in the case of emergency services. In parallel, the technology has evolved from Circuit Switch (CS) to Packet Switch (PS) networks requiring backwards compatibility. As a result the emergency services support for NGNs, in particular for IMS, is being standardized by 3GPP, NENA, ETSI. In this paper we present architecture for Emergency Services support in IMS, starting from the one from 3GPP. We have implemented this architecture as the Emergency Branch of the open-source project Open IMS Core. The available methods for personalizing the testbed and validation scenarios are described here. More important, the management of resource allocation and prioritization of emergency calls is also discussed in the context of the emerging EPC.

Integrating Wireless Sensor & Actuator Networks (WS&AN) on a large scale allows horizontal applications to access real-world information in real-time and changing the state of the real world, thus providing the basis for the Real World Internet. In this paper we present a resource model that semantically describes sensor, actuator and processing resources for the Real World Internet, this model is designed to efficiently support information queries and execute actuation requests in a large scale system.

The Always Best Connected Systems (ABCS) philosophy, in which different access technologies coexist, allows the user to select at any time an appropriate network that is optimized for the current service. To study this scenario through simulations, it is needed that all simulators are system-level type. Regarding this point, Effective SNR Mapping (ESM) algorithms provide the link layer abstraction that is crucial for the system level simulation interface. In this paper we have used the Mutual Information Effective SNR Mapping (MIESM) algorithm for instantaneous-channel modelling, calibration and evaluation of the Link Level Interface in the WiMAX System 802.16e together with a realistic Mobile WiMAX simulator. Plenty of simulations were performed to evaluate different algorithms and the results show that MIESM gives higher accuracy than the rest of ESM methods.