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The future wireless communications is expected to integrate different link layer technologies and to allow the most appropriate network to be selected depending on different criteria. Mobile nodes (MN) may want to discover neighbouring networks and detailed parameters before it moves into the coverage areas of the candidate networks, focusing on the optimisation of handover processes. In the IEEE 802.21 standard, a media independent information service (MIIS) is developed providing network information within a geographical area. However, the MIIS focuses on the static information (channel information, service provider name, network type supported, etc.). Dynamic information includes link-layer parameters such as available network resources, throughput, data rate, etc. This paper proposes a dynamic information server mesh architecture (DISMA) for realtime collection, discovery and sharing of dynamic network information. With DISMA, the MN is able to retrieve real-time dynamic information using a decentralised MIIS framework. Finally, this distributed approach generates an important advantage regarding the scalability and robustness if compared with the traditional centralised scheme. This paper also provides NS-2 simulation results and analytical models to prove the feasibility and performance of DISMA scheme.

Designing routing protocols for Mobile Ad Hoc Networks (MANETs) is a complex task because of its dynamic topology. A kind of routing protocols that suits the particularity of MANETs is so–called bio–inspired. Among these, focused on Ant Colony Optimisation (ACO), which studies the behaviour of ants in their search for food, are especially relevant. One of these algorithms is AntOR, which relying on swarm intelligence, efficiently solves routing in MANETs. In this paper we show a parallelised version of AntOR, the so–called P–AntOR, that using programming multiprocessor architectures based on shared memory protocol, allows to run tasks in parallel using threads, being applicable this parallelisation in the route discovery phase, route local repair process and link failure notification. The simulation results indicate that P–AntOR performs better than its predecessor, with emphasis on the metric of average End–To–End delay, jitter and packet delivery ratio.

This paper presents a new mechanism of QoS Medium Access in ad hoc IEEE 802.11 network. The Distributed Coordination Function Ad Hoc (DCFAH) offers a fair medium access mechanism and a minimum bandwidth to all stations that ask for Quality of Service (QoS). Also is concerned about the delay and jitter metrics. The DCFAH uses the Enhanced Distributed Channel Access (EDCA) mechanism to provide the difference of QoS services among flows inside a station. The fairness of DCFAH is provided with the use of a distributed control mechanism during the QoS period. The DCFAH also provides the Best Effort (BE) service to applications that do not need QoS.