Task Recovery in Self-Organised Multi-Agent Systems for Distributed Domains

Grid computing and cloud systems are distributed systems which provide substantial widely-accessible services to resources. Quality of service is affected by the issues around resource allocation, sharing, task execution and node failure. The focus of this research is on task execution in distributed environments and the effects of node failure on service provision. Most methods in the literature which provide fault tolerance, use reactive techniques; these provide solutions to failure only after its occurrence. In contrast, this research argues that using multi-agent systems with self-organising capabilities can provide a proactive methodology which can improve task execution in open, dynamic and distributed environments. We have modelled a system of autonomous agents with heterogeneous resources and proposed a new delegation protocol for executing tasks within their time constraints. This helps avoid the loss of tasks and to improve efficiency. However, this method on its own is not sufficient in terms of task execution throughput, especially in the presence of agent failure. Hence, we propose, a self-organisation technique. This is represented in this research by two different mechanisms for creating organisations of agents with a certain structure; we suggest, in addition, the adoption of task delegation within the organisations. Adding an organisation structure with agent roles to the network enables smoother performance, increases task execution throughput and copes with agent failures. In addition, we study the failure problem as it manifests within the organisations and we suggest an improvement to the organisation structure which involves the use of another protocol and adding a new role. An exploratory study of dynamic, heterogeneous organisations of agents has also been conducted to understand the formation of organisations in a dynamic environment where agents may fail and new agents may join organisations. These conditions mean that new organisations may evolve and existing organisations may change

Tailoring e-commerce sites to ease recovery after disruptions

Developers of e-commerce applications are often unrealistic about how their Web site is going to be used, and about possible outcomes during site usage. The most commonly considered outcomes of a user's visit to a site are firstly that the visit culminates in a sale, and secondly that the user leaves the site without buying anything - perhaps to return later. In the second case, sites often "remember" any accumulated items so that a shopper can return at a later stage to resume shopping. In this paper, we consider certain disruptions, such as breakdowns, problems caused by human errors and interruptions, which could affect the outcome of the e-commerce shopping experience. These events have definite and possibly long-lasting effects on users, and applications should therefore be developed to cater for these eventualities so as to enhance the usability of the site and encourage further usage. We develop a model for analysing e-commerce application usage and, using this model, propose an evaluation strategy for determining whether an e-commerce site is resistant to such factors. The proposed evaluation mechanism is applied to three sites to arrive at what we call a "disruption-resistance score"

Recommendations for changes in UK National Recovery Guidance (NRG) and associated guidance from the perspective of Lancaster University's Hull Flood Studies

This report was commissioned by the Civil Contingencies Secretariat (CCS) following the publication of Lancaster University‟s Hull Flood Project and Hull Children‟s Flood Project. Its principal purpose is to identify how findings made as a result of the two research projects could be integrated into the Cabinet Office‟s National Recovery Guidance (NRG), as a means to improve affected communities‟ ability to recover from emergency events. The report, in effect, details a desktop analysis of UK Civil Protection (CP) guidance, from a bottom-up perspective (i.e. using as its critical lens, the lived experiences of members of the public who were tested by the Hull flooding of 2007 and its aftermath)

Enhancing Enterprise Resilience through Enterprise Collaboration

Current environments, characterised by turbulent changes and unforeseen events, consider resilience as a decisive aspect for enterprises to create advantages over less adaptive competitors. Furthermore, the consideration of establishing collaborative processes among partners of the same network is a key issue to help enterprises to deal with changeable environments. In this paper both concepts, resilience and collaborative processes establishment, are associated in order to help organisations to handle disruptive events. The research objective is to identify collaborative processes whose positive influences assist enterprises against disruptions, reducing the effects of disturbances in dynamic environments.Andres, B.; Poler R. (2013). Enhancing Enterprise Resilience through Enterprise Collaboration. IFAC papers online. 7(1):688-693. doi:10.3182/20130619-3-RU-3018.00283S6886937

Deploying self-organisation to improve task execution in a multi-agent systems

This paper discusses how the performance of a network of agents can be improved using a self-organisation technique. The multi-agent network performance can be improved by organizing the agents in clusters. Furthermore, principles of self-organisation can be used to create agent organisations triggered when some of the agents have high load. Hence, busy agents within the network may decide to create an organisation to receive extra support from other less busy agents in order to execute more tasks. The paper presents a simulation based on Repast Simphony that has been used to develop the proposed model and describes a set of experiments showing the performance of the system with and without the self-organisation technique

Observing the clouds : a survey and taxonomy of cloud monitoring

This research was supported by a Royal Society Industry Fellowship and an Amazon Web Services (AWS) grant. Date of Acceptance: 10/12/2014Monitoring is an important aspect of designing and maintaining large-scale systems. Cloud computing presents a unique set of challenges to monitoring including: on-demand infrastructure, unprecedented scalability, rapid elasticity and performance uncertainty. There are a wide range of monitoring tools originating from cluster and high-performance computing, grid computing and enterprise computing, as well as a series of newer bespoke tools, which have been designed exclusively for cloud monitoring. These tools express a number of common elements and designs, which address the demands of cloud monitoring to various degrees. This paper performs an exhaustive survey of contemporary monitoring tools from which we derive a taxonomy, which examines how effectively existing tools and designs meet the challenges of cloud monitoring. We conclude by examining the socio-technical aspects of monitoring, and investigate the engineering challenges and practices behind implementing monitoring strategies for cloud computing.Publisher PDFPeer reviewe

Survival in the e-conomy: 2nd Australian information warfare & security conference 2001

This is an international conference for academics and industry specialists in information warfare, security, and other related fields. The conference has drawn participants from national and international organisations