Abstract
A Wireless Mesh Network (WMN) is an effective solution to provide Internet connectivity to large areas and its efficiency may increase if multiple radio channels are used in the mesh backbone. This paper proposes a protocol for centralized channel assignment in single-radio WMNs. This protocol has the capability to discover all the links available between Mesh Access Points (MAPs), independently of the channel they operate. With this information, a network manager can assign the right channel to each MAP in order to, for instance, maximize the network throughput. The proposed protocol extends WiFIX [1] which is a low overhead solution for implementing IEEE 802.11-based WMNs. © 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.

Abstract
Accurate localization 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, localization methods will enable a number of applications and processes to substantially reduce human intervention. In this paper 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. The existing GSM infrastructure and tunnel conditions seem to be favorable to the adoption of these Fingerprinting methods. Nevertheless significant variations in the signal have been observed which might be traced back to different operational states of accelerator equipment. These effects and their sources will be analyzed in more detail in order to improve the applied techniques and their accuracy under such challenging conditions.

Abstract
The growth of available broadband access technologies has brought an enormous challenge for operators wanting to ensure seamless mobility to its customers in heterogeneous environments. In this paper we present an enhanced Mobility Management entity focused on a real heterogeneous environments and based on IEEE802.21 standard. This entity is capable to perform terminal and handover management regardless the access technology used. This entity was deployed in a real heterogeneous environment with Wi-Fi, WiMAX and HSPA using an Android smartphone. In order to provide Layer 3 mobility support it was integrated with a modified version of MIPv6. The results show not only the impact of a centralized entity to manage vertical handovers, but also the performance of IEEE802.21 protocol in a real scenario with a real implementation. ©2011 IEEE © 2011 IEEE.© 2011 IEEE.

Abstract
Explicit congestion control (XCC) is emerging as one potential solution for overcoming limitations inherent to the current TCP algorithm, characterized by unstable throughput, high queuing delay, RTT-limited fairness, and a static dynamic range that does not scale well to high bandwidth delay product networks. In XCC, routers provide multibit feedback to sources, which, in turn, adapt throughput more accurately to the path bandwidth with potentially faster convergence times. Such systems, however, require precise knowledge of link capacity for efficient operation. In the presence of variable-capacity media, e.g., 802.11, such information is not entirely obvious or may be difficult to extract. We explore three possible algorithms for XCC which retain efficiency under such conditions by inferring available bandwidth from queue dynamics and test them through simulations with two relevant XCC protocols: XCP and RCP. Additionally, preliminary results from an experimental implementation based on XCP are presented. Finally, we compare our proposals with TCP and show how such algorithms outperform it in terms of efficiency, stability, queuing delay, and flow-rate fairness.

Abstract
Wireless Sensor Networks (WSNs) for medical purposes enables real-time (RT) acquisition of vital signals. In this context the network reliability, data integrity and RT delivery have extreme importance. The network should guarantee an appropriate level of Quality of Service (QoS). This paper presents the QoS parameters and metrics of standard telemedicine and WSNs based Medical Applications (MA), and a strategy, based on QoS monitoring, to prevent QoS degradation in WSNs for MA.

Abstract