Abstract
Localisation techniques have long been of major importance for safety systems and a lot of research has been conducted in the distributed computing field regarding its functionality and reliability. In the specific scenario of long yet narrow tunnels existing at CERN, localisation methods will enable a number of applications and processes to substantially reduce human intervention. In this article, we evaluate the use of fingerprinting techniques with GSM signal available throughout the LHC tunnel via a radiating cable and compare some methods to estimate the location. In the tests, 16 variants of the K-Nearest Neighbour algorithm, employing different distance weighting methods and fingerprint grouping functions, are taken into consideration and their performance is assessed with a specific rating algorithm. The existing GSM infrastructure and tunnel conditions seem to be favourable to the adoption of these fingerprinting methods. Nevertheless, significant variations in the signal have been observed which might be traced back to the presence of bulky equipment and different operational states of the accelerator. The performance limits of these fingerprinting methods are discussed for the current scenario and, based on that, an outlook for future research is given aiming at improving the system's accuracy under such challenging conditions. © 2012 Copyright Taylor and Francis Group, LLC.

Abstract
This paper quantifies the impact of topological characteristics on the performance of single radio multichannel IEEE 802.11 mesh networks. Topological characteristics are the number of nodes per subnetwork, the hop count, the neighbor node density, the hidden nodes, the number of nodes in the neighborhood of the gateway, and the hidden nodes in the neighborhood of the gateway. Network performance metrics are throughput, fairness and delay. The data mining Support Vector Machine (SVM) model was used to extract the relationships between the network topology metrics and the network performance metrics based on data results obtained through ns-2 simulation of random networks. The results obtained can be used as a basis to design channel assignment algorithms or to aid the deployment and management of single radio wireless mesh networks.

Abstract
Future public transportation systems will provide broadband access to passengers, carrying legacy terminals with 802.11 connectivity. Passengers will be able to communicate with the Internet and with each other, while connected to 802.11 Access Points deployed in vehicles and bus stops/metro stations, and without requiring special mobility or routing protocols to run in their terminals. Existing solutions, such as 802.11s and OLSR, are not efficient and do not scale to large networks, thereby requiring the network to be segmented in many small areas, causing the terminals to change IP address when moving between areas. This paper presents WiMetroNet, a large mesh network of mobile routers (Rbridges) operating at layer 2.5 over heterogeneous wireless technologies. This architecture contains an efficient user plane that optimizes the transport of DHCP and ARP traffic, and provides a transparent terminal mobility solution using techniques that minimize the routing overhead for large networks. We offer two techniques to reduce routing overhead associated with terminal mobility. One approach is based on TTL-limited flooding of a routing message and on the concept of forwarding packets only to the vicinity of the last known location of the terminal, and then forward the packets to a new location of the terminal. The other technique lets the network remain unaware for a very long time that the terminal has moved; only when packets arrive at the old PoA does the PoA send back a "binding update" message to the correspondent node, to correct the route for future packets for the same terminal. Simulation and analytical results are presented, and the routing protocol is shown to scale to large networks with good user plane results, namely packet delivery rate, delay, and handover interruption time.

Abstract
Interconnection of different access network technologies is an important research topic in mobile telecommunications systems. In this paper, we propose an ns-3 architecture for simulating the interconnection of wireless local area network (WLAN) and Universal Mobile Telecommunications System (UMTS). This architecture is based on the architecture proposed by the Third Generation Partnership Project, being the use of virtual interfaces as its main innovation. In order to demonstrate the value of the proposed simulation framework, we implemented the UMTS and WLAN interconnection considering three joint radio resource management strategies for distributing arriving calls. From the simulations results, we can conclude that the proposed simulation architecture is suitable to test and evaluate performance aspects related to the interconnection and joint management of UMTS and WLAN technologies. Copyright (c) 2012 John Wiley & Sons, Ltd.

Abstract
Nowadays it's common to find the same place covered by multiple access networks. For that reason, mobile terminals are normally equipped with multiple network interfaces, which allow users to take advantage of the heterogeneity of those networks. This paper presents an architecture capable of using, in a simultaneous way, the multiple network interfaces existent in the mobile terminal for accessing a video streaming service. With this goal in mind, a solution on the session layer was developed, allowing the creation of an abstraction layer for the intervening applications. The purposed solution is composed by two modules, responsible for the division and aggregation of the transmitted data through multiple interfaces. The obtained results show that the developed architecture is not only capable of interconnecting two machines through multiple interfaces in a simultaneous way, but it is also capable of processing a video stream division in an intelligent way, accordingly to the network conditions. © 2012 University of Split.

Abstract
A Biomedical Wireless Sensor Network (BWSN) is a special Wireless Sensor Network (WSN) with a small number of nodes designed for medical applications. These networks must ensure that medical data is delivered reliably and efficiently, M order to fulfil a sel of pre-established Quality of Service (QoS) requirements, In this way, the research community have been proposing new solutions to improve QoS in WSN, namely in routing protocols and power consumption efficiency. However, there slid a need for appropriate QoS guaranties ha BWSN. In this paper, possible QoS requirements of BWSN are discussed, together with a framework to automatically evaluate the performance of such QoS techniques. That framework was used together with simulators and operating systems appropriate for WSN, COOJA and Contiki OS, and proved to be a valuable tool for a proper evaluation of QoS parameters and metrics.