In many parts of the world, the electricity supply industry makes the task of dealing with unpredictable spikes and dips in production and demand invisible to consumers, maintaining a seemingly unlimited supply. A future increase in reliance on time-variable renewable sources of electricity may lead to greater fluctuations in supply. We engaged remote islanders as equal partners in a research project that investigated through technology-mediated enquiry the topic of synchronising energy consumption with supply, and together built a prototype renewable energy forecast display. A number of participants described a change in their practices, saving high energy tasks for times when local renewable energy was expected to be available, despite having no financial incentive to do so. The main contributions of this paper are in: 1) the results of co-development sessions exploring systems supporting synchronising consumption with supply and 2) the findings arising from the deployment of the prototype.

Social Software Engineering (Social SE), that is SE aiming to promote positive social change, is a rapidly emerging area. Here, software and digital artefacts are seen as tools for social change, rather than end products or 'solutions'. Moreover, Social SE requires a sustained buy-in from a range of stakeholders and end-users working in partnership with multidisciplinary software development teams often at a distance. This context poses new challenges to software engineering: it requires both an agile approach for handling uncertainties in the software development process, and the application of participatory, creative design processes to bridge the knowledge asymmetries and the geographical distances in the partnership. This paper argues for the role of design thinking in Social SE and highlights its implications for software engineering in general. It does so by reporting on the contributions that design thinking -- and in particular physical design -- has brought to (1) the problem space definition, (2) user requirements capture and (3) system feature design of a renewable energy forecasting system developed in partnership with a remote Scottish Island community.

Service-Oriented Computing (SOC) has rapidly progressed in recent years, with examples appearing in numerous application areas including business processes, high-performance computing, web-based services, and embedded systems. In the embedded systems domain, ubiquitous devices, context-aware systems, and sensor networks are increasingly being used in a plethora of areas. However, because of the nature of their operating environment, service-oriented embedded systems (SOeS) pose unique challenges to quality management. SOeS have to contend not only with the quality of services from providers, but also with the constrained system resources in their operating environment. SOeS need to efficiently utilise available system resources by dynamically adapting themselves to changes in their runtime environment. This paper discusses current SOC resource-management initiatives, setting out the challenges that SOeS systems must overcome, and proposes a pluggable, runtime resource-management framework for SOeS.

An increasing trend in mobile and pervasive computing is the augmentation of everyday public spaces with local computation - leading to so called smart environments. However, there are no well accepted techniques for supporting spontaneous interaction between mobile users and these smart environments, though a wide range of techniques have been explored ranging from gesture recognition to downloading applications to a user's phone. In this paper we explore an approach to supporting such interaction based on the use of Bluetooth Device (user-friendly) Names as a control channel between users' mobile phones and computational resources in their local environment. Such an approach has many advantages over existing techniques though it is not without limitations. Our work focuses specifically on the use of Device Names to control and customize applications on large public displays in a campus environment. This paper describes our basic approach, a number of applications that we have constructed using this technique and the results of our evaluation work which has included a range of user studies and field trials. The paper concludes with an assessment of the viability of using our approach for interaction scenarios involving mobile users and computationally rich environments.

Internet protocol (IP) traffic on the Internet and private enterprise networks has been growing exponentially for some time. This growth is beginning to stress the traditional processor-based design of current-day routers. Switching technology offers much higher aggregate bandwidth, but presently only offers a layer-2 bridging solution. Various proposals are under way to support IP routing over an asynchronous transfer mode (ATM) network. However, these proposals hide the real network topology from the IP layer by treating the data-link layer as a large opaque network cloud. We argue that this leads to complexity, inefficiency, and duplication of functionality in the resulting network. We propose an alternative in which we discard the end-to-end ATM connection and integrate fast ATM hardware directly with IP, preserving the connectionless nature of IP. We use the soft-state in the ATM hardware to cache the IP forwarding decision. This enables further traffic on the same IP flow to be switched by the ATM hardware rather than forwarded by IP software. We claim that this approach combines the simplicity, scalability, and robustness of IP, with the speed, capacity, and multiservice traffic capabilities of ATM.

A number of proposals for supporting the Internet protocol (IP) over ATM are under discussion in the networking community including: LAN emulation, classical IP over ATM, routing over large clouds, and multiprotocol over ATM. Each of these proposals hides the real network topology from the IP layer by treating the data link layer as a large, opaque, network cloud. We argue that this leads to complexity, inefficiency and duplication of functionality in the resulting network. We propose an alternative in which we discard the connection oriented nature of ATM and integrate fast ATM hardware directly with the IP, presenting the connectionless nature of the IP. We use a "soft" state in the ATM hardware to cache the IP forwarding decision. This enables further traffic on the same IP flow to be switched by the ATM hardware rather than forwarded by the IP software. We claim that this approach combines the simplicity, scalability, and robustness of the IP with the speed, capacity, and multiservice traffic capabilities of ATM.

An investigation is presented of the performance, for multiservice traffic, of a high-capacity, fast packet switch based on a nonbuffered, multistage interconnection network, implemented from identical LSI switching elements. It is shown that for an implementation operating at 30 Mb/s, switches with a total traffic capacity of up to 50 Gb/s can be constructed. If the voice class traffic load is limited on each switch port to a maximum of 80% of saturation, a maximum delay across the switch of on the order of 200 mu s can be guaranteed, for every voice-class connection, regardless of the total traffic load on the switch.>

With the projected growth in demand for bandwidth and telecommunication services will come the requirement for a multiservice backbone network of far greater efficiency, capacity, and flexibility than ISDN (integrated-services digital network) is able to satisfy. This class of network has been termed the broadband ISDN, and the design of the switching nodes of such a network is the subject of much research. The author investigates one possible solution. The design and performance, for multiservice traffic, is presented for a fast packet switch based on a nonbuffered, multistage interconnection network. It is shown that for an implementation in current CMOS technology, operating at 50 MHz, switches with a total traffic capacity of up to 150 Gb/s can be constructed. Furthermore, if the reserved service traffic load is limited on each input port to a maximum of 80% of switch port saturation, then a maximum delay across the switch of on the order of 100 mu s can be guaranteed, for 99% of the reserved service traffic, regardless of the unreserved service traffic load.>