Distributed and intelligent routing algorithm

A Network's topology and its routing algorithm are the key factors in determining the network performance. Therefore, in this thesis a generic model for implementing logical interconnection topologies in the software domain has been proposed to investigate the performance of the logical topologies and their routing algorithms for packet switched synchronous networks. A number of topologies are investigated using this model and a simple priority rule is developed to utilise the usage of the asymmetric 2 x 2 optical node. Although, logical topologies are ideal for optical (or any other) networks because of their relatively simple routing algorithms, there is a requirement for much more flexible algorithms that can be applied to arbitrary network topologies. Antnet is a software agent based routing algorithm that is influenced by the unsophisticated and individual ant's emergent behaviour. In this work a modified antnet algorithm for packet switched networks has been proposed that offers improvement in the packet throughput and the average delay time. Link usage information known as "evaporation" has also been introduced as an additional feedback signal to the algorithm to prevent stagnation within the network for the first time in the literature for the best our knowledge. Results show that, with "evaporation" the average delay experienced by the data packets is reduced nearly 30% compared to the original antnet routing algorithm for all cases when non-uniform traffic model is employed. The multiple ant colonies concept is also introduced and applied to packet switched networks for the first time which has increased the packet throughput. However, no improvement in the average packet delay is observed in this case. Furthermore, for the first time extensive analysis on the effect of a confidence parameter is produced here. A novel scheme which provides a more realistic implementation of the algorithms and flexibility to the programmer for simulating communication networks is proposed and used to implement these algorithms

Distributed and intelligent routing algorithm

A Network's topology and its routing algorithm are the key factors in determining the network performance. Therefore, in this thesis a generic model for implementing logical interconnection topologies in the software domain has been proposed to investigate the performance of the logical topologies and their routing algorithms for packet switched synchronous networks. A number of topologies are investigated using this model and a simple priority rule is developed to utilise the usage of the asymmetric 2 x 2 optical node. Although, logical topologies are ideal for optical (or any other) networks because of their relatively simple routing algorithms, there is a requirement for much more flexible algorithms that can be applied to arbitrary network topologies. Antnet is a software agent based routing algorithm that is influenced by the unsophisticated and individual ant's emergent behaviour. In this work a modified antnet algorithm for packet switched networks has been proposed that offers improvement in the packet throughput and the average delay time. Link usage information known as "evaporation" has also been introduced as an additional feedback signal to the algorithm to prevent stagnation within the network for the first time in the literature for the best our knowledge. Results show that, with "evaporation" the average delay experienced by the data packets is reduced nearly 30% compared to the original antnet routing algorithm for all cases when non-uniform traffic model is employed. The multiple ant colonies concept is also introduced and applied to packet switched networks for the first time which has increased the packet throughput. However, no improvement in the average packet delay is observed in this case. Furthermore, for the first time extensive analysis on the effect of a confidence parameter is produced here. A novel scheme which provides a more realistic implementation of the algorithms and flexibility to the programmer for simulating communication networks is proposed and used to implement these algorithms.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Logical rings in the mutual exclusion problem of distributed memory systems

In this thesis, we investigate distributed mutual exclusion algorithms and delineate the features of a new distributed mutual exclusion algorithm. The basis of the algorithm is the logical ring structure employed in token-based mutual exclusion algorithms. Specifically, there exists dynamic properties of the logical ring that, given certain restrictions regarding message traffic flow, passively give useful information about the location of the token. Effectively, the algorithm demonstrates a type of intelligent routing that identifies useful shortcuts to in the routing of the token. The result is a reduction in the total number of messages exchanged prior to the execution of the critical section as compared to the algorithm proposed by Fu and Tzeng (7). Furthermore, the algorithm allows for an increased degree of fairness in a lightly loaded system than that allowed by Fu and Tzeng\u27s algorithm

Pervasive intelligent routing in content centric delay tolerant networks

This paper introduces a Swarm-Intelligence based Routing protocol (SIR) that aims to efficiently route information in content centric Delay Tolerant Networks (CCDTN) also dubbed pocket switched networks. First, this paper formalizes the notion of optimal path in CCDTN and introduces an original and efficient algorithm to process these paths in dynamic graphs. The properties and some invariant features of these optimal paths are analyzed and derived from several real traces. Then, this paper shows how optimal path in CCDTN can be found and used from a fully distributed swarm-intelligence based approach of which the global intelligent behavior (i.e. shortest path discovery and use) emerges from simple peer to peer interactions applied during opportunistic contacts. This leads to the definition of the SIR routing protocol of which the consistency, efficiency and performances are demonstrated from intensive representative simulations

Robotic Wireless Sensor Networks

In this chapter, we present a literature survey of an emerging, cutting-edge, and multi-disciplinary field of research at the intersection of Robotics and Wireless Sensor Networks (WSN) which we refer to as Robotic Wireless Sensor Networks (RWSN). We define a RWSN as an autonomous networked multi-robot system that aims to achieve certain sensing goals while meeting and maintaining certain communication performance requirements, through cooperative control, learning and adaptation. While both of the component areas, i.e., Robotics and WSN, are very well-known and well-explored, there exist a whole set of new opportunities and research directions at the intersection of these two fields which are relatively or even completely unexplored. One such example would be the use of a set of robotic routers to set up a temporary communication path between a sender and a receiver that uses the controlled mobility to the advantage of packet routing. We find that there exist only a limited number of articles to be directly categorized as RWSN related works whereas there exist a range of articles in the robotics and the WSN literature that are also relevant to this new field of research. To connect the dots, we first identify the core problems and research trends related to RWSN such as connectivity, localization, routing, and robust flow of information. Next, we classify the existing research on RWSN as well as the relevant state-of-the-arts from robotics and WSN community according to the problems and trends identified in the first step. Lastly, we analyze what is missing in the existing literature, and identify topics that require more research attention in the future

Machine Learning in Wireless Sensor Networks: Algorithms, Strategies, and Applications

Wireless sensor networks monitor dynamic environments that change rapidly over time. This dynamic behavior is either caused by external factors or initiated by the system designers themselves. To adapt to such conditions, sensor networks often adopt machine learning techniques to eliminate the need for unnecessary redesign. Machine learning also inspires many practical solutions that maximize resource utilization and prolong the lifespan of the network. In this paper, we present an extensive literature review over the period 2002-2013 of machine learning methods that were used to address common issues in wireless sensor networks (WSNs). The advantages and disadvantages of each proposed algorithm are evaluated against the corresponding problem. We also provide a comparative guide to aid WSN designers in developing suitable machine learning solutions for their specific application challenges.Comment: Accepted for publication in IEEE Communications Surveys and Tutorial

Study on QoS support in 802.11e-based multi-hop vehicular wireless ad hoc networks

Multimedia communications over vehicular ad hoc networks (VANET) will play an important role in the future intelligent transport system (ITS). QoS support for VANET therefore becomes an essential problem. In this paper, we first study the QoS performance in multi-hop VANET by using the standard IEEE 802.11e EDCA MAC and our proposed triple-constraint QoS routing protocol, Delay-Reliability-Hop (DeReHQ). In particular, we evaluate the DeReHQ protocol together with EDCA in highway and urban areas. Simulation results show that end-to-end delay performance can sometimes be achieved when both 802.11e EDCA and DeReHQ extended AODV are used. However, further studies on cross-layer optimization for QoS support in multi-hop environment are required