Integration of Internet and Telecommunications- An Architecture for Hybrid Services

In this article, we propose an architecture for hybrid services, i.e., services that span many network technologies, such as the Public Switched Telephone Network (PSTN), cellular networks and networks based on the Internet Protocol (IP). These services will play an important role in the future because they leverage on the existing infrastructures, rather than requiring new and sophisticated mechanisms to be deployed. We explore a few issues related to hybrid services and propose a platform, as well as a set of components, to facilitate their creation and deployment. The existing infrastructure is only required to generate specific events when requests for hybrid services are detected. We present the design of a service layer, based on Java, that handles the treatment of these special requests. Our service layer is provided with a set of generic components realized according to the JavaBeans model. We illustrate the strength of our architecture by discussing two hybrid-service examples: a calendar service and a call forwarding service

A Goal-Directed and Policy-Based Approach to System Management

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, http://www.cs.stir.ac.uk/accent) 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, http://www.cs.stir.ac.uk/appel). 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

Exploring conflicts in rule-based Sensor Networks

This paper addresses rule conflicts within wireless sensor networks. The work is situatedwithin psychiatric ambulatory assessment settings where patients are monitored in andaround their homes. Detecting behaviours within these settings favours sensor networks,while scalability and resource concerns favour processing data on smart nodes incorporatingrule engines. Such monitoring involves personalisation, thereby becoming important toprogram node rules on the fly. Since rules may originate from distinct sources and changeover time, methods are required to maintain rule consistency. Drawing on lessons fromFeature Interaction, the paper contributes novel approaches for detecting and resolving rule-conflict across sensor networks

Conflict Detection in Call Control using First-Order Logic Model Checking

Feature interaction detection methods, whether online or offline, depend on previous knowledge of conflicts between the actions executed by the features. This knowledge is usually assumed to be given in the application domain. A method is proposed for identifying potential conflicts in call control actions, based on analysis of their pre/post-conditions. First of all, pre/postconditions for call processing actions are defined. Then, conflicts among the pre/post-conditions are defined. Finally, action conflicts are identified as a result of these conflicts. These cover several possibilities where the actions could be simultaneous or sequential. A first-order logic model-checking tool is used for automated conflict detection. As a case study, the APPEL call control language is used to illustrate the approach, with the Alloy tool serving as the model checker for automated conflict detection. This case study focuses on pre/post-conditions describing call control state and media state. The results of the method are evaluated by a domain expert with pragmatic understanding of the system’s behavior. The method, although computationally expensive, is fairly general and can be used to study conflicts in other domains

An Online Environmental Approach to Service Interaction Management in Home Automation

Home automation is maturing with the increased deployment of networks and intelligent devices in the home. Along with new protocols and devices, new software services will emerge and work together releasing the full potential of networked consumer devices. Services may include home security, climate control or entertainment. With such extensive interworking the phenomenon known as service interaction, or feature interaction, appears. The problem occurs when services interfere with one another causing unexpected or undesirable outcomes. The main goal of this work is to detect undesired interactions between devices and services while allowing positive interactions between services and devices. If the interaction is negative, the approach should be able to handle it in an appropriate way. Being able to carry out interaction detection in the home poses certain challenges. Firstly, the devices and services are provided by a number of vendors and will be using a variety of protocols. Secondly, the configuration will not be fixed, the network will change as devices join and leave. Services may also change and adapt to user needs and to devices available at runtime. The developed approach is able to work with such challenges. Since the goal of the automated home is to make life simpler for the occupant, the approach should require minimal user intervention. With the above goals, an approach was developed which tackles the problem. Whereas previous approaches solving service interaction have focused on the service, the technique presented here concentrates on the devices and their surrounds, as some interactions occur through conflicting effects on the environment. The approach introduces the concept of environmental variables. A variable may be room temperature, movement or perhaps light. Drawing inspiration from the Operating Systems domain, locks are used to control access to the devices and environmental variables. Using this technique, undesirable interactions are avoided. The inclusion of the environment is a key element of this approach as many interactions can happen indirectly, through the environment. Since the configuration of a home’s devices and services is continually changing, developing an off-line solution is not practical. Therefore, an on-line approach in the form of an interaction manager has been developed. It is the manager’s role to detect interactions. The approach was shown to work successfuly. The manager was able to successfully detect interactions and prevent negative interactions from occurring. Interactions were detected at both device and service level. The approach is flexible: it is protocol independent, services are unaware of the manager, and the manager can cope with new devices and services joining the network. Further, there is little user intervention required for the approach to operate

A System for Controlling, Monitoring and Programming the Home

As technology becomes ever more pervasive, the challenges of home automation are increasingly apparent. Seamless home control, home monitoring and home programming by the end user have yet to enter the mainstream. This could be attributed to the challenge of developing a fully autonomous and extensible home system that can support devices and technologies of differing protocols and functionalities. In order to offer programming facilities to the user, the underlying rule system must be fully independent, allowing support for current and future devices. Additional challenges arise from the need to detect and handle conflicts that may arise among user rules and yield undesirable results. Non-technical individuals typically struggle when faced with a programming task. It is therefore vital to encourage and ease the process of programming the home. This thesis presents Homer, a home system that has been developed to support three key features of a home system: control, monitoring and programming. Homer supports any third-party hardware or software service that can expose its functionality through Java and conform to the Homer interface. Stand-alone end user interfaces can be written by developers to offer any of Homer's functionality. Where policies (i.e. rules) for the home are concerned, Homer offers a fully independent policy system. The thesis presents a custom policy language, Homeric, that has been designed specifically for writing home rules. The Homer policy system detects overlaps and conflicts among rules using constraint satisfaction and the effect on environment variables. The thesis also introduces the notion of perspectives to ease user interactivity. These have been integrated into Homer to accommodate the range of ways in which a user may think about different aspects and features of their home. These perspectives include location, device type, time and people-oriented points of view. Design guidelines are also discussed to aid end user programming of the home. The work presented in this thesis demonstrates a system that supports control, monitoring and programming of the home. Developers can quickly and easily add functionality to the home through components. Conflicts can be detected amongst rules within the home. Finally, design guidelines and a prototype interface have been developed to allow both technically minded and non-technical people to program their home

Towards Personalised Home Care Systems

Home care is increasingly seen as a promising alternative to traditional care services. Programming home care systems remains a significant challenge considering the potentially large scale of deployment, the differences between individual care needs, and the progressive nature of ageing. In this paper, we present ongoing work on programming home care systems to support personalisation, adaptability over time, and dependability. A policy-based approach is used to build such systems. We present the technical details of our approach, including a policy language for home care and the corresponding system architecture. Policy examples are used to illustrate how the approach supports personalisation of home care services