A Reliability-based Framework for Multi-path Routing Analysis in Mobile Ad-Hoc Networks

Unlike traditional routing procedures that, at the best, single out a unique route, multi-path routing protocols discover proactively several alternative routes. It has been recognized that multi-path routing can be more efficient than traditional one mainly for mobile ad hoc networks, where route failure events are frequent. Most studies in the area of multi-path routing focus on heuristic methods, and the performances of these strategies are commonly evaluated by numerical simulations. The need of a theoretical analysis motivates such a paper, which proposes to resort to the terminal-pair routing reliability as performance metric. This metric allows one to assess the performance gain due to the availability of route diversity. By resorting to graph theory, we propose an analytical framework to evaluate the tolerance of multi-path route discovery processes against route failures for mobile ad hoc networks. Moreover, we derive a useful bound to easily estimate the performance improvements achieved by multi-path routing with respect to any traditional routing protocol. Finally, numerical simulation results show the effectiveness of this performance analysis.Comment: To appear on IJCNDS: International Journal of Communication Networks and Distributed System

Brisa: combining efficiency and reliability in epidemic data dissemination

There is an increasing demand for efficient and robust systems able to cope with today's global needs for intensive data dissemination, e.g., media content or news feeds. Unfortunately, traditional approaches tend to focus on one end of the efficiency/robustness design spectrum, by either leveraging rigid structures such as trees to achieve efficient distribution, or using loosely-coupled epidemic protocols to obtain robustness. In this paper we present BRISA, a hybrid approach combining the robustness of epidemic-based dissemination with the effi- ciency of tree-based structured approaches. This is achieved by having dissemination structures such as trees implicitly emerge from an underlying epidemic substrate by a judicious selection of links. These links are chosen with local knowledge only and in such a way that the completeness of data dissemination is not compromised, i.e., the resulting structure covers all nodes. Failures are treated as an integral part of the system as the dissemination structures can be promptly compensated and repaired thanks to the underlying epidemic substrate. Besides presenting the protocol design, we conduct an extensive evaluation in a real environment, analyzing the effectiveness of the structure creation mechanism and its robustness under faults and churn. Results confirm BRISA as an efficient and robust approach to data dissemination in the large scale.This work was supported in part by the Swiss National Foundation under agreement number 200021-127271/1 and by the Portuguese Science Foundation (FCT) grants SFRH/BD/62380/2009 and PTDC/EIA-CCO/115570/200

Traffic engineering multi-layer optimization for wireless mesh network transmission a campus network routing protocol transmission performance inhancement

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel UniversityThe wireless mesh network is a potential network for the future due to its excellent inherent characteristic for dynamic self-healing, self-configuration and self-organization. It also has the advantage of easy interoperability networking and the ability to form multi-linked ad-hoc networks. It has a decentralized topology, is cheap and highly scalable. Furthermore, its ease in deployment and easy maintenance are other inherent networking qualities. These aforementioned qualities of the wireless mesh network bring advantages to transmission capability of heterogeneous networks. However, transmissions in wireless mesh network create comparative performance based challenges such as congestion, load-balancing, scalability over increasing networks and coverage capacity. Consequently, these challenges and problems in the routing and switching of packets in the wireless mesh network routing protocols led to a proposal on the resolution of these failures with a combination algorithm and a management based security for the network and its transmitted packets. There are equally contentious services like reliability of the network and quality of service for real-time multimedia traffic flows with other challenges such as path computation and selection in the wireless mesh network. This thesis is therefore a cumulative proposal to the resolution of the outlined challenges and open research areas posed by using wireless mesh network routing protocol. It advances the resolution of these challenges in the mesh environment using a hybrid optimization – traffic engineering, to increase the effectiveness and the reliability of the network. It also proffers a cumulative resolution of the diverse contributions on wireless mesh network routing protocol and transmission. Adaptation and optimization are carried out on the wireless mesh network designed network using traffic engineering mechanism and technique. The research examines the patterns of mesh packet transmission and evaluates the challenges and failures in the mesh network packet transmission. It develops a solution based algorithm for resolutions and proposes the traffic engineering based solution.. These resultant performances and analysis are usually tested and compared over wireless mesh IEEE802.11n or other older proposed documented solution. This thesis used a carefully designed campus mesh network to show a comparative evaluation of an optimal performance of the mesh nodes and routers over a normal IEE802.11n based wireless domain network to show differentiation by optimization using the created algorithms. Furthermore, the indexes of performance being the metric are used to measure the utility and the reliability, including capacity and throughput at the destination during traffic engineered transmission. In addition, the security of these transmitted data and packets are optimized under a traffic engineered technique. Finally, this thesis offers an understanding to the security contribution using traffic engineering resolution to create a management algorithm for processing and computation of the wireless mesh networks security needs. The results of this thesis confirmed, completed and extended the existing predictions with real measurement

Genetic programming hyper-heuristic with vehicle collaboration for uncertain capacitated arc routing problem

Due to its direct relevance to post-disaster operations, meter reading and civil refuse collection, the Uncertain Capacitated Arc Routing Problem (UCARP) is an important optimisation problem. Stochastic models are critical to study as they more accurately represent the real world than their deterministic counterparts. Although there have been extensive studies in solving routing problems under uncertainty, very few have considered UCARP, and none consider collaboration between vehicles to handle the negative effects of uncertainty. This article proposes a novel Solution Construction Procedure (SCP) that generates solutions to UCARP within a collaborative, multi-vehicle framework. It consists of two types of collaborative activities: one when a vehicle unexpectedly expends capacity (route failure), and the other during the refill process. Then, we propose a Genetic Programming Hyper-Heuristic (GPHH) algorithm to evolve the routing policy used within the collaborative framework. The experimental studies show that the new heuristic with vehicle collaboration and GP-evolved routing policy significantly outperforms the compared state-of-the-art algorithms on commonly studied test problems. This is shown to be especially true on instances with larger numbers of tasks and vehicles. This clearly shows the advantage of vehicle collaboration in handling the uncertain environment, and the effectiveness of the newly proposed algorithm

Balancing Performance, Robustness and Flexibility in Routing Systems

Modern networks face the challenging task of handling increasingly diverse traffic that is displaying a growing intolerance to disruptions. This has given rise to many initiatives, and in this paper we focus on multiple topology routing as the primary vehicle for meeting those demands. Specifically, we seek routing solutions capable of not just accommodating different performance goals, but also preserving them in the presence of disruptions. The main challenge is computational, i.e., to identify among the enormous number of possible routing solutions the one that yields the best compromise between performance and robustness. This is where our principal contribution lies, as we expand the definition of critical links -- a key concept in improving the efficiency of routing computation -- and develop a precise methodology to efficiently converge on those solutions. Using this new methodology, we demonstrate that one can compute routing solutions that are both flexible in accommodating different performance requirements and robust in maintaining them in the presence of failures and traffic fluctuations

A Parallel Fast-Track Service Restoration Strategy Relying on Sectionalized Interdependent Power-Gas Distribution Systems

In the distribution networks, catastrophic events especially those caused by natural disasters can result in extensive damage that ordinarily needs a wide range of components to be repaired for keeping the lights on. Since the recovery of system is not technically feasible before making compulsory repairs, the predictive scheduling of available repair crews and black start resources not only minimizes the customer downtime but also speeds up the restoration process. To do so, this paper proposes a novel three-stage buildup restoration planning strategy to combine and coordinate repair crew dispatch problem for the interdependent power and natural gas systems with the primary objective of resiliency enhancement. In the proposed model, the system is sectionalized into autonomous subsystems (i.e., microgrid) with multiple energy resources, and then concurrently restored in parallel considering cold load pick-up conditions. Besides, topology refurbishment and intentional microgrid islanding along with energy storages are applied as remedial actions to further improve the resilience of interdependent systems while unpredicted uncertainties are addressed through stochastic/IGDT method. The theoretical and practical implications of the proposed framework push the research frontier of distribution restoration schemes, while its flexibility and generality support application to various extreme weather incidents.©2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.fi=vertaisarvioitu|en=peerReviewed