Recent Technical Reports
The following Departmental Technical Reports were published from 2009 onwards. There is another page for reports published before 2009.
Where the author of a report below is highlighted as a link, click on it to contact the author (via home web page or email). Some reports are available for downloading. Click on the symbol preceding each article for the following:
Paper copies of reports may be requested from:
For large reports (typically PhD theses) a nominal charge is made to cover copying and postage.
Title: Can People Program Their Home?
Author(s): Claire Maternaghan
Date: April 2012
Number: CSM-191
Abstract:
The requirements of a home system vary greatly in terms of the residents, the existing devices available, and many other factors. It is therefore crucial that any home system can be customisable by the end user; ideally this process would be simple and quick to perform. However, the challenges of end user programming are enormous. There is considerable challenge in obtaining concrete and unambiguous rules from non-technically minded individuals who typically think, and express, their desires as high level goals. Additionally, the language that is used to express the home rules must enable simple rules to be written by those less technical or ambitious, yet also not restrict more competent users.
Homer is a home system that has been fully developed by the author. It offers the ability for users to control, monitor and program their home. A custom policy language has been designed called Homeric which allows rules to be written for the home.
In order to evaluate Homeric, and the design guidelines for allowing end users to formulate Homeric, a stand-alone application was written. This application is called the Homeric Wizard and allows rules to be expressed for the home. It makes use of natural language and visual programming techniques, as well as the notion of perspectives which allows rule elements to be browsed from differing aspects – devices, locations, people and time.
An online evaluation was performed over two weeks, obtaining participation from 71 individuals of varying age, gender, status and technical abilities. This report presents an evaluation of the Homeric Wizard tool, and all the results and hypotheses obtained.
Title: A Peer-to-Peer Network Framework utilising The
Public Mobile Telephone Network (MPhil Thesis)
Author(s): Martin Blunn
Date: December 2011
Number: CSM-190
Keywords: Wireless Sensor Network, Middleware
Abstract:
P2P (Peer-to-Peer) technologies are well established and have now become accepted as a mainstream networking approach. However, the explosion of participating users has not been replicated within the mobile networking domain. Until recently the lack of suitable hardware and wireless network infrastructure to support P2P activities was perceived as contributing to the problem. This has changed with ready availability of handsets having ample processing resources utilising an almost ubiquitous mobile telephone network. Coupled with this has been a proliferation of software applications written for the more capable 'smartphone' handsets. P2P systems have not naturally integrated and evolved into the mobile telephone ecosystem in a way that 'client-server' operating techniques have. However as the number of clients for a particular mobile application increase, providing the 'server side' data storage infrastructure becomes more onerous. P2P systems offer mobile telephone applications a way to circumvent this data storage issue by dispersing it across a network of the participating users handsets.
The main goal of this work was to produce a P2P Application Framework that supports developers in creating mobile telephone applications that use distributed storage. Effort was assigned to determining appropriate design requirements for a mobile handset based P2P system. Some of these requirements are related to the limitations of the host hardware, such as power consumption. Others relate to the network upon which the handsets operate, such as connectivity. The thesis reviews current P2P technologies to assess which was viable to form the technology foundations for the framework. The aim was not to re-invent a P2P system design, rather to adopt an existing one for mobile operation. Built upon the foundations of a prototype application, the P2P framework resulting from modifications and enhancements grants access via a simple API (Applications Programmer Interface) to a subset of Nokia 'smartphone' devices. Unhindered operation across all mobile telephone networks is possible through a proprietary application implementing NAT (Network Address Translation) traversal techniques.
Recognising that handsets operate with limited resources, further optimisation of the P2P framework was also investigated. Energy consumption was a parameter chosen for further examination because of its impact on handset participation time.
This work has proven that operating applications in conjunction with a P2P data storage framework, connected via the mobile telephone network, is technically feasible. It also shows that opportunity remains for further research to realise the full potential of this data storage technique.
Title: Language Definition for REED
Author(s): Xiang Fei and Evan H. Magill
Date: May 2011
Number: CSM-189
Keywords: Wireless Sensor Network, Middleware
Abstract:
Wireless Sensor Networks (WSNs) have emerged as an enabling technology for a variety of distributed applications. WSN middleware eases the development of these applications by providing a uniform programming environment. REED (Rule Execution and Event Distribution) is WSN middleware that supports both the distribution of rules and the events that trigger them. This report provides the full description of the REED language that is defined using a variant of BNF (Backus-Naur Form).
Title: The Accent Policy System
Author(s): Kenneth J. Turner
Date: May 2011
Number: CSM-188 (Revised)
Keywords: ACCENT (Advanced Component Control Enhancing
Network Technologies), APPEL policy language (ACCENT Project Policy
Environment/Language), Goal, OSGi (Open Systems Gateway initiative), Policy
Abstract:
This report describes the architecture, installation and configuration of the ACCENT policy system. It is seen that virtually all the ACCENT components are bundles deployed on an OSGi system. These bundles communicate using the OSGi event service. The details are given of how to set up and configure each of the bundles.
Title: The Homer Home Automation System
Author(s): Claire Maternaghan
Date: December 2010
Number: CSM-187
Abstract:
This report discusses Homer, a system developed for managing home automation and telecare. The philosophy and architecture of Homer are explained. The nature of home components is discussed, along with how they fit together into the overall system. Policies are used as a means of automated decisions based on user-defined rules for control of the home system. User-friendly interfaces for home management are then presented. Finally, the report summarises what has been covered, evaluates the current status of home automation and telecare, and identifies trends and future developments in these fields.
Title: An Integrated Methodology for Creating Composed Web/Grid Services (PhD Thesis)
Author(s): Koon Leai Larry Tan
Date: October 2010
Number: CSM-186
Abstract:
This thesis presents an approach to design, specify, validate, verify, implement, and evaluate composed web/grid services. Web and grid services can be composed to create new services with complex behaviours. The BPEL (Business Process Execution Language) standard was created to enable the orchestration of web services, but there have also been investigations of its use for grid services. BPEL specifies the implementation of service composition but has no formal semantics; implementations are in practice checked by testing. Formal methods are used in general to define an abstract model of system behaviour that allows simulation and reasoning about properties. The approach can detect and reduce potentially costly errors at design time.
CRESS (Communication Representation Employing Systematic Specification) is a domain-independent, graphical, abstract notation, and an integrated toolset for developing composite web services. The original version of CRESS had automated support for formal specification in LOTOS (Language Of Temporal Ordering Specification), executing formal validation with MUSTARD (Multiple-Use Scenario Testing and Refusal Description), and implementation using BPEL4WS as the early version of the BPEL standard. This thesis work has extended CRESS and its integrated tools to design, specify, validate, verify, implement, and evaluate composed web/grid services. The work has extended the CRESS notation to support a wider range of service compositions, and has applied it to grid services as a new domain. The thesis presents two new tools: CLOVE (CRESS Language-Oriented Verification Environment) and MINT (MUSTARD Interpreter). These respectively support formal verification and implementation testing. New work has also extended CRESS to automate implementation of composed services using the more recent BPEL standard WS-BPEL 2.0.
Title: How do People want to control Their Home?
Author(s): Claire Maternaghan
Date: April 2011
Number: CSM-185
Abstract:
There are a large number of home automation companies which offer consumers tailored solutions to meet their exact needs. At installation time users are asked how they would like their home to behave so that the company engineers can program the solution for their client. Once programmed, the users must contact the company and, in many cases, pay for these rules to be altered in any way. This is mostly due to the rigid design of the software architecture used by these companies. In most cases the user is very unlikely to know how they would like their home to behave until they have lived with the technology for some time. Even then, their requirements may change on a daily basis.
The author proposes that consumers need home systems that they are able to program, and re-program, easily. In order to gain a deeper understanding of how people could see themselves using such a control mechanism of their home, an online survey was carried out. There were 150 participants ranging in age, gender, technical ability and experience. This report describes the survey and user group, and then explores the data received from the survey: evaluating the author's eight hypotheses and exploring any trends in the qualitative data gathered.
Title: An Analysis of Planarity in Face-Routing
Author(s): Marwan M. Fayed, David E. Cairns
and Hussein T. Moutfah
Date: August 2010
Number: CSM-184
Abstract:
In this report we investigate the limits of routing according to left- or right-hand rule (LHR). Using LHR, a node upon receipt of a message will forward to the neighbour that sits next in counter-clockwise order in the network graph. When used to recover from greedy routing failures, LHR guarantees success if implemented over planar graphs. This is often referred to as face or geographic routing. In the current body of knowledge it is known that if planarity is violated then LHR is guaranteed only to eventually return to the point of origin. Our work seeks to understand why a non-planar environment stops LHR from making delivery guarantees. Our investigation begins with an analysis to enumerate all node con gurations that cause intersections. A trace over each con guration reveals that LHR is able to recover from all but a single case, the `umbrella' con guration so named for its appearance. We use this information to propose the Prohibitive Link Detection Protocol (PDLP) that can guarantee delivery over non-planar graphs using standard face-routing techniques. As the name implies, the protocol detects and circumvents the `bad' links that hamper LHR. The goal of this work is to maintain routing guarantees while disturbing the network graph as little as possible. In doing so, a new starting point emerges from which to build rich distributed protocols in the spirit of protocols such as CLDP and GDSTR.
Title: Case Studies using Cress to develop Web and
Grid Services
Author(s): Koon Leai Larry Tan
Date: December 2009
Number: CSM-183
Abstract:
Web and grid services are forms of distributed computing based on the SOA (Service-Oriented Architecture) paradigm which offers loose coupling of functionality and interoperability in heterogeneous environments, achieved by using standards such as SOAP (Simple Object Access Protocol) and WSDL (Web Services Description Language). Web and grid services are widely used in businesses and research, where functionality is usually missioncritical. Services may be combined to create new services, an activity generally known as service composition. There are standards such as WS-BPEL (Web Services – Business Process Execution Language) that implement service composition. There is increasing implementation of web/grid services and their compositions, with more complex behaviour being developed.
Formal techniques support mathematical reasoning about the behaviour of systems which can detect errors and identify issues prior to implementation, and therefore can minimise the potential cost of errors as early as possible. Formal techniques can be applied to web and grid service composition. However, the attention given to their use is, by contrast, far less than the practical realisation of service implementation. Two reasons for this are the lack of formal expertise, and methodological differences between the practices of formal methods and service implementation.
CRESS (Communication Representation Employing Systematic Specification) is an abstract graphical notation and toolset for describing services at a high level, whereby specifications and implementations are automatically generated. CRESS has been extended for web and grid service compositions with automated support for specification, analysis, implementation and testing that appeals to nonspecialists. Service behaviour is automatically specified in LOTOS (Language of Temporal Ordering Specification). Formal analysis is supported in a manner appealing to non-specialists by abstracting formal aspects using high-level languages; analysis is carried out automatically.
These formal analyses, in the forms of validation and verification, are supported by MUSTARD (Multiple–Use Scenario Testing and Refusal Description) and CLOVE (CRESS Language-Oriented Verification Environment). Implementations of (composed) web and grid services are generated as Java and BPEL services, for deployment in Axis (web services), Globus Toolkit (grid services), and ActiveBPEL (BPEL services). Implementation analysis in the form of validation is supported by MINT (MUSTARD Interpreter), which is a high-level notation and tool that automates testing and performance evaluation on implemented services. These are integrated with CRESS, providing an integrated environment for service development in a rigorous way.
This report demonstrates the integrated methodology using web and grid service compositions as case studies.
Title: An Ontology Based Approach Towards A Universal
Description Framework for Home Networks (PhD Thesis)
Author(s): Liam S. Docherty
Date: February 2010
Number: CSM-182
Abstract:
Current home networks typically involve two or more machines sharing network resources. The vision for the home network has grown from a simple computer network to every day appliances embedded with network capabilities. In this environment devices and services within the home can interoperate, regardless of protocol or platform. Network clients can discover required resources by performing network discovery over component descriptions. Common approaches to this discovery process involve simple matching of keywords or attribute/value pairings.
Interest emerging from the Semantic Web community has led to ontology languages being applied to network domains, providing a logical and semantically rich approach to both describing and discovering network components. In much of the existing work within this domain, developers have focused on defining new description frameworks in isolation from existing protocol frameworks and vocabularies.
This work proposes an ontology-based description framework which takes the ontology approach to the next step, where existing description frameworks are incorporated into the ontology-based framework, allowing discovery mechanisms to cover multiple existing domains. In this manner, existing protocols and networking approaches can participate in semantically-rich discovery processes. This framework also includes a system architecture developed for the purpose of reconciling existing home network solutions with the ontology-based discovery process.
This work also describes an implementation of the approach and is deployed within a home-network environment. This implementation involves existing home networking frameworks, protocols and components, allowing the claims of this work to be examined and evaluated from a 'real-world' perspective.
Title: Directed Intervention Crossover Approaches in
Genetic Algorithms with Application to Optimal Control Problems (PhD
Thesis)
Author(s): Paul Godley
Date: May 2009
Number: CSM-181
Abstract:
Genetic Algorithms (GAs) are a search heuristic technique modelled on the processes of evolution. They have been used to solve optimisation problems in a wide variety of fields. When applied to the optimisation of intervention schedules for optimal control problems, such as cancer chemotherapy treatment scheduling, GAs have been shown to require more fitness function evaluations than other search heuristics to find fit solutions. This thesis presents extensions to the GA crossover process, termed directed intervention crossover techniques, that greatly reduce the number of fitness function evaluations required to find fit solutions, thus increasing the effectiveness of GAs for problems of this type.
The directed intervention crossover techniques use intervention scheduling information from parent solutions to direct the offspring produced in the GA crossover process towards more promising areas of a search space. By counting the number of interventions present in parents and adjusting the number of interventions for offspring schedules around it, this allows for highly fit solutions to be found in less fitness function evaluations.
The validity of these novel approaches is illustrated through comparison with conventional GA crossover approaches for optimisation of intervention schedules of bio-control application in mushroom farming and cancer chemotherapy treatment. These involve optimally scheduling the application of a bio-control agent to combat pests in mushroom farming and optimising the timing and dosage strength of cancer chemotherapy treatments to maximise their effectiveness.
This work demonstrates that significant advantages are gained in terms of both fitness function evaluations required and fitness scores found using the proposed approaches when compared with traditional GA crossover approaches for the production of optimal control schedules.
Title: A Goal-Directed and Policy-Based Approach to
System Management (PhD Thesis)
Author(s): Gavin A. Campbell
Date: May 2009
Number: CSM-180
Abstract:
This thesis presents a domain-independent approach to dynamic system management using goals and policies. A goal is a general, high-level aim a system must continually work toward achieving. A policy is a statement of how a system should behave for a given set of detectable events and conditions. Combined, goals may be realised through the selection and execution of policies that contribute to their aims. In this manner, a system may be managed using a goal-directed, policy-based approach.
The approach is a collection of related techniques and tools: a policy language and policy system, goal definition and refinement via policy selection, and conflict filtering among policies. Central to these themes, ontologies are used to model application domains, and incorporate domain knowledge within the system. The ACCENT policy system (Advanced Component Control Enhancing Network Technologies) is used as a base for the approach, while goals and policies are defined using an extension of APPEL (Adaptable and Programmable Policy Environment and Language).
The approach differs from existing work in that it reduces system state, goals and policies to a numerical rather than logical form. This is more user-friendly as the goal domain may be expressed without any knowledge of formal methods. All developed techniques and tools are entirely domain-independent, allowing for reuse with other event-driven systems. The ability to express a system aim as a goal provides more powerful and proactive high-level management than was previously possible using policies alone. The approach is demonstrated and evaluated within this thesis for the domains of Internet telephony and sensor network/wind turbine management.
Title: A Case Study in Integrated Assertion
Verification with Omnibus
Author(s): Thomas Wilson, Savi Majaraj, Robert G. Clark
Date: January 2009
Number: CSM-176
Keywords: Static Checking, Run-Time Checking,
Integrated Formal Methods, Object-Oriented Programming
Abstract:
We present the example of the specification, implementation, and verification of a library system in Omnibus. Three approaches to verification (run-time assertion checking, extended static checking, and full formal verification) are applied to the example. We compare the ease of use and the error coverage of each approach. We then discuss how the three approaches may be used together within Omnibus in an integrated manner, explain the benefits of this, and show how integration is supported by the Omnibus IDE.
Title: The Accent Policy Wizard
Author(s): Kenneth J. Turner
Date: June 2011 (Revised)
Number: CSM-166
Abstract:
The Accent project (Advanced Component Control Enhancing Network Technologies) developed a practical and comprehensive policy system for call control/Internet telephony. The policy system has subsequently been extended for management of sensor networks/wind farms on the Prosen project (Proactive Control of Sensor Networks). The policy system has also been extended for management of home care/telecare on the Match project (Mobilising Advanced Technologies for Care at Home).
This report focuses on a web-based policy wizard that acts as the primary interface between end users and the policy system. The policy wizard has an intimate knowledge of the Appel policy language (Adaptable and Programmable Policy Environment and Language). The wizard makes use of domain-specific ontologies so that it can be used in any application. The wizard allows end users to create policies using near-natural language without knowing or seeing XML, and to upload them to the policy system. The wizard also provides a number of convenience functions such as predefined policy templates, editing and activating existing policies, and defining policy variables. Besides regular policies, the wizard supports resolution policies for handling conflicts among policy actions.
Title: The Accent Policy Server
Author(s): Stephan Reiff-Marganiec, Kenneth J.
Turner, Lynne Blair and Feng Wang
Date: July 2011 (Revised)
Number: CSM-164
Abstract:
The Accent project (Advanced Call Control Enhancing Networked Systems) was concerned with developing a practical and comprehensive policy language for call control. The project studied a number of distinct tasks: the definition of the language, and also a three-layer architecture for deploying and enforcing policies defined in the language. The approach was subsequently extended for home care and telecare on the Match project (Mobilising Advanced Technologies for Care at Home) and for sensor networks and wind farms on the Prosen project (Proactive Control of Sensor Networks).
This document focuses on the policy system layer of the architecture. The layer is concerned with storing, deploying and enforcing policies. It represents the core functionality of the three-layer architecture. This report discusses the prototype implementation at a technical level. It is intended as supporting documentation for developers continuing to enhance the policy server, as well as those wishing to gain an insight into the technical details of the policy server layer.
Title: Appel: An Adaptable and Programmable Policy Environment and
Language
Author(s):
Kenneth J.
Turner, Stephan Reiff-Marganiec, Lynne
Blair, Gavin A. Campbell and Feng Wang
Date: May 2011 (Revised)
Number: CSM-161
Abstract:
The Accent project (Advanced Component Control Enhancing Network Technologies) developed a practical and comprehensive policy system for call control/Internet telephony. The policy system has subsequently been extended for management of sensor networks/wind farms and of home care/telecare.
This report focuses on Appel (Adaptable and Programmable Policy Environment and Language). It provides an overview of the language, and presents the language in XML schema form. The core language has been instantiated for call control, for sensor networks, and for home care. Sample goals and policies of different kinds are provided to illustrate these applications.
