Showing papers in "Bt Technology Journal in 2002"

The future of fibre access systems

Abstract: It is clear that there is a huge potential demand for high bandwidth services that, at some point in the future, could be delivered over the fixed network. The most promising technology to provide the delivery mechanism to the customer is optical access networks. The major issue for the telecommunications industry is how to do this at sufficiently low cost. This paper looks at the economic issues and suggests some possible ways forward if we are to move to delivery of services well beyond the capability of ADSL and cable-modem technologies.

Domesticating Broadband — What Consumers Really Do with Flat-Rate, Always-On and Fast Internet Access

Abstract: This paper reports analysis of a range of survey, interview and usage-log data on the level of use of broadband Internet by households in the UK and Europe. It discusses the (few) discernable differences between PSTN and broadband Internet users in mid 2001. The analysis suggests that, while there are few socio-economic and demographic differences, broadband users tend to use a wider range of applications, access them more frequently and for longer. However, because most broadband users have been, on average, users of the Internet for longer than PSTN users, these effects may be to do with their Internet competencies rather than the nature of broadband Internet itself. The paper also suggests that the interaction of speed, flat rate and 'always-on' is a key feature of broadband and a key value model to the user. The paper concludes by discussing the implications of the usage patterns of these early adopters for current and future portal, application and service investment strategy.

A method for the manual extraction of business rules from legacy source code

Abstract: One of the main barriers to the successful migration of legacy systems is lack of information about the system to be migrated. With the complexity of modern information systems, it is rarely the case that an organisation has a complete end-to-end understanding of its systems, business processes and information. This is particularly true of the business rules enforced by such systems, which are often poorly documented (if at all) and incompletely understood by those who own, use and maintain such systems. These business rules must be migrated, along with the other system functionality, but this is difficult when they are buried deep within the source code of the system. In this paper, we propose a method for the discovery of business rules through inspection of the source code of legacy systems. We also describe the results of a comprehensive evaluation exercise undertaken within BT, in which the method was applied to a legacy system about to undergo migration. The results of this study indicated considerable success for the method in extracting valid business rules, but also highlighted some weaknesses. Most significantly, the cost of applying the method is a factor of the size and complexity of the system being analysed, and not of the number of business rules elicited. In order to address this, we propose a cut-down version of the method that can be used to produce a quick estimate of the likely yield of business rules from a program. Together, these two forms of the method aid personnel engaged in system migration projects in making maximum use of the scarce resources are available for business rule discovery.

Digital Living — People-Centred Innovation and Strategy

Abstract: This paper provides a summary of a research programme at BTexact Technologies which is aimed at helping a technology innovation company to ground its innovations, to see opportunities for the exploitation of its technologies, and to create socio-technical visions which can help to drive technological innovation itself. As a by-product, the programme has also created strategic knowledge that is of critical importance to public and private policy/decision makers alike. This research is a key part of BTexact Technologies' approach to the creation of and response to disruptive technologies. Understanding ‘usage by people’ is absolutely critical to figuring out what is disruptive about technologies, why this is so, and therefore how to make money out of them. Since this is critical to several of BTexact's core competencies (and to those of its customers), the value of the research reported here is self-evident both to BTexact and to its customers. Without it, they will only ever make money by accident, a strategy that shareholders do not seem to find amusing.

Residential Gateways

Abstract: The residential gateway (RG) is set to become a key infrastructure component in the future home network. Ideally home networks should be easy to set up and operate and it should also be possible to securely deliver and manage services. For service providers, the RG appears to offer a huge opportunity to extend their presence into the home and in so doing ‘own’ the territory. However, a new generation of customers are used to retaining control and many people will be unwilling to let external agents intrude too far into their environment. This paper examines the residential gateway, the forms it might take, the roles it could play and looks at aspects of management.

Computer Vision for a 3-D Visualisation and Telepresence Collaborative Working Environment

Abstract: An integrated media system is a computer-based environment that supports the creation, sharing, distribution and effective communication of multimodal information across the boundaries of space and time. The EU Information Societies Technology (IST) project — VIRTUE (Virtual Team User Environment) is working steadily towards the realisation of most aspects and properties of such a system, with particular emphasis on a three-way semi-immersive telepresence videoconferencing scenario. In contrast with the traditional videoconferencing system that we know now, the outcome of the project is expected to demonstrate distinctive presence features and experience for the conference participants. These include views of full-body-size realistically rendered images, eye-to-eye contact, gaze awareness, normal hand gesturing and direct body language. The purpose of this paper is to describe the current work in its related technical field, and the main objectives and scope of this project. One optional software system framework is outlined, and also illustrated are some component technologies in 3-D computer vision analysis that are being developed. The application of these component technologies, notably the dense-disparity estimation and the novel view synthesis, in 3-D interactive video manipulation and visualisation, are widely expected.

Satellite — A New Opportunity for Broadband Applications

Abstract: This paper provides an overview of the new and exciting opportunities that satellite creates for the delivery of true broadband Internet and multimedia content directly to the edge of the network or to the end user. A current snapshot of the different satellite delivery topologies is given, followed by an appraisal of the underlying protocol aspects on which these satellite topologies are built. This paper then reviews the various broadband applications that can be effectively delivered via satellite, exploiting satellite's natural broadcasting and ubiquitous coverage characteristics. These aspects are then expanded further by a discussion of the key security options that must be considered when designing such networks.

Bandwidth-On-Demand Networks — A Solution to Peer-To-Peer File Sharing

Abstract: An important driver for the take-up of broadband services has been peer-to-peer file-sharing programs like Napster, which enables users to freely share around music and now video files. This is putting network operators and service providers in an awkward position as they are under pressure to shut down or limit access to such applications, as the majority are operating illegally since the content owner does not get any revenue. Current activities to protect copyright focuses on either keeping the contents secure (digital rights management) or tackling the distribution mechanisms via the courts. Neither of these are complete solutions. This paper describes a third way which utilises bandwidth-on-demand network capabilities to make content sharing more controllable. Although this will not prevent video piracy completely, it should discourage it sufficiently to minimise the problem. This should also appeal to network operators as bandwidth is still relatively expensive. The network solutions developed to prove the concept build on the capabilities in the current ATM-based ADSL network, but an option for an all-IP network is also described.

Adaptive Network Overload Controls

Abstract: Network overloads can seriously degrade the quality or availability of telecommunications services if they are not effectively controlled. This paper explains why overload controls are required and how they should behave for both today's and future networks. The requirements of overload controls are presented, in terms of the conditions under which they must operate and the behaviour they should exhibit. Good design principles are proposed, which include identifying the controlled variable, the control structure, convergence and stability, and parameter configuration, while ensuring that different implementations work together. Relevant network standards are highlighted, and the paper stresses the crucial importance that these standards adequately specify the behaviour of overload controls.

Finding the Killer Application — The Role of the Broadband Applications Laboratory

Abstract: The world of the Internet is experiencing its next revolution — broadband access. It is recognised that fast Internet access alone is insufficient to drive broadband connectivity, and that, ultimately, compelling applications will create demand. But what will these compelling applications look like and how will one find them? This paper examines how a killer application will have to surpass a number of technological, economic and sociological issues in order to be a success, and how it is likely that the application presented to the user will comprise a number of sub-applications, potentially glued together using Web services as an enabling technology. The paper also outlines the Broadband Applications Laboratory (BAL) as a unique facility that can assist in the discovery, evaluation, development, test and rapid deployment of the killer application by providing a dedicated team and supporting infrastructure to take applications from inception through to launch. Finally the paper describes 'Software-To-Go', a trial of an applications-on-demand service that could just be one of the killer applications — not only does it fulfil many of the requirements of a killer application, but it also neatly encapsulates the capabilities of the BAL.

Performance Modelling — What, Why, When and How

Abstract: Management of performance risk is achieved by using performance engineering techniques. A major weapon in the performance engineering armoury is performance modelling. Modelling means prediction — estimating the performance of a new system, estimating the impact of change on an existing system or estimating the impact of a change of workload on an existing system. This paper describes how IT systems performance modelling fits into the overall performance engineering approach and its role in performance prediction and risk management. It then focuses on a recent case study illustrating why a particular modelling technique was used, how it was used, and the outcome of the modelling exercise.

Traffic Characterisation and Modelling

Abstract: New and emerging systems and networks are increasingly rich in functionality. Their usage — that is, the traffic and demands upon them — has become correspondingly more complex and unstable than that of older systems; and the traditional broad-brush descriptions of network behaviour are now far from adequate. Traffic modelling is not an arid statistical description of observed gross volumes, but rather the detailed probabilistic description of the small-scale structure of demand which is essential for the performance assessment of these new systems. This paper is an overview of the field of traffic modelling in its own right, and sets out and discusses some of the techniques that are now an essential part of the armoury of the professional performance engineer when assessing any new network or system. It is devoted principally to the study of traffic itself, as the underlying driver of all performance models; but a number of examples of applications are included for illustrative purposes.

Home Area Network Technologies

Abstract: This paper describes the current home networking technologies, some background to their origins, a brief review of how they work and what benefits they bring to the home. Each review concludes with the advantages and disadvantages of the particular networking technology. The role of residential gateways is described, along with example architectures. Finally, some of the Internet-aware devices which are available today are discussed.

Storage area networking – an introduction and future development trends

Abstract: This paper presents a detailed overview of the current and future networking options within the storage arena. Particular emphasis is placed on exploring strategic storage solutions, which are based on metropolitan area network (MAN) deployments, with respect to market influences, transmission evolution, and mediation. Evolution of storage networking is moving towards a connecting role between multiple SAN islands and enterprise networks, across geographically dispersed networks. This connection-based role can be typically over WANs or MANs and can be achieved in a number of ways – dark fibre point-topoint, ATM/SDH circuits and WDM. This paper focuses on what are believed to be the key technologies and evolutionary trends in this area, and discusses storage-based issues relating to optical networking, WDM, SDH, ATM, as well as connectivity over IP.

Fibre to the home – infrastructure deployment issues

Abstract: To date the use of optical fibre in the access network has typically only proved cost effective for supplying the high-bandwidth demands of large corporate companies. For new and established network operators, however, the increasing demand for bandwidth to deliver bearer, interactive and bundled services to business and residential customers is requiring them to seriously consider the high volume roll-out of optical-fibre-based systems. Network operators therefore face some major decisions, not only in terms of the type of fibre transmission systems to deploy, but also on how to install a cost-effective network of fibre cables, ducting and joints to connect to the customers they wish to serve. Installing fibre in the ground represents a major commitment and a long term investment. Network operators can typically expected the fibre infrastructure to equate to at least 60% of the cost of the overall access transmission system. Planning and building such networks involves major investment at the outset, and, in today”s highly competitive markets, operators are faced with the added complications of uncertain take-up of services by customers and the likelihood of high customer churn. This paper focuses on “fibre to the home” (FTTH) and the deployment options and challenges for the physical fibre infrastructure. The key difference associated with connecting optical fibre to residential properties instead of business properties is not technical but commercial. There is typically a much smaller potential revenue from a residential property than from a business property. This leads to a need for cost optimisation of both the transmission system and the fibre infrastructure. This paper examines the fibre infrastructure issues that need to be considered for an FTTH deployment and describes the fibre access network modelling activities carried out by BTexact's Broadband Network Engineering unit. The aim of this modelling is both to automate the planning of, and to optimise the costs of deploying, access networks based on real geographical and demographic data.

Realising Effective Intelligent Network Overload Controls

Abstract: The traffic attracted by intelligent network (IN) services is often volatile in nature. Many IN realisations have a centralised physical architecture (although the standards only define the functional architecture in a distributed way), which means that they are vulnerable to overload from incoming traffic, which it is therefore essential to control. An IN platform typically has a processing capacity much greater than each network destination to which it routes traffic. Therefore control of outgoing traffic is necessary as well. IN standards only define a means to carry control messages — they do not provide methods to achieve effective overload control. This paper presents overload control designs which integrate these principles and thus meet fundamental requirements such as bounding response times and limiting ineffective traffic, while maximising the occupancy of network destinations. It is also shown how control parameter values may be optimised by appropriate modelling.

Ultra-Long-Haul WDM transmission systems

Abstract: This paper discusses the key transmission issues and design considerations for ultra-long-haul WDM systems. The key enabling technologies for the current generation of ultra-long-haul WDM transmission are described. Noise analysis and transmission modelling results are presented, and an overview of the developing transmission technology is also given.

Personal Virtual Humans — Inhabiting the TalkZone and beyond

Abstract: One of the fundamental goals of graphics has always been to visually create a three-dimensional person that is indistinguishable from a real person. This target is only slightly short of being reached, as was demonstrated when Columbia Pictures released Final Fantasy in 2001, an animated science fiction film with high-definition emotive characters. Through what has been a cultural and technological convergence, we are now starting to see software tools and techniques that can generate life-like characters while not sacrificing the human judgement and artistic skills that are needed in character animation. Computer games, films, and the Internet are now starting to use virtual humans, which as our conclusion will show will become more realistic. However, a new challenge has been set — people now do not want to just play a computer game with a visually realistic character, or see a television programme with a vivid computer generated character — they want to see themselves in that computer game or film. The future is towards individuals having their own virtual clones, which they can utilise in computer-generated worlds an applications. This paper will discuss the advantages of having a personal computer-generated character, and also describe several systems that BTexact Technologies have successfully developed and deployed to generate them, as well as some of the applications for which they can be used. The paper will finish by glimpsing into the future of what we can expect to see in the next few years, with the advent of this new exciting technology.

Optical metropolitan DWDM networks an overview

Abstract: The paper deals with the subject of how to build a core network in the current technology scenario. We start with an overview of what we consider a core network, not in an abstract way but referring to real country situations, and pointing out the different aspects conditioning its realisation – population distribution, territory shape, traffic characteristics. In the next section a summary of different network topologies is presented and briefly analysed – rings, meshes, loosely or tightly interconnected, with particular attention to the resilience aspect in case of faults. The following section is dedicated to a short presentation of the current technology scenario and how it reflects on the network elements (NEs) offered on the market (OXC, OADM, PXC, etc). Finally, the question is posed: “What is the best way to implement a core network?” with the conclusion being that there is no single answer – each situation must be pursued on a case-by-case basis. This paper describes some important aspects of next-generation metropolitan networking, with special focus on market drivers and applications, upcoming standards like GFP and GMPLS, required functionalities like optical switching and protection, and a generic view on a next-generation platform.

Broadband in the Home

Abstract: Despite the fact that well over half the population is now served by ADSL-equipped exchanges (at March 2002 there were 1010 exchanges enabled for broadband), the take-up of broadband, particularly in the home, is very low. By March 2002 there were 145 000 customers signed up for broadband; a year ago there were only 40 000. Clearly price is a key factor in the decision-making process and recent announcements from the BT Group lowering the wholesale price of asymmetric digital subscriber line (ADSL) should enable the market to grow more quickly and compete with product offerings from other providers such as cable. However, it is not just about price. To really feel the expenditure is worthwhile, the user must believe that they are getting genuine benefits from the service as they exploit the potential of the additional bandwidth. To do this effectively, some form of home distribution is required. Due to the potential diversity of the services that could be offered, some type of home gateway that is straightforward to install and use is also a necessity. Various solutions exist today which could help fulfil this role, e.g. the PC, a set-top box, a router, etc, but in reality it is likely that all these functions need to be combined in a low-cost, consumer-oriented package. This paper examines the practical problems of installing broadband in the home, the need for a self-install option, the development of a practical home network and the need for a home gateway.

Techniques for the Study of QoS in IP Networks

Abstract: Setting the many parameters available to the operator in a QoS-enabled IP network in order to achieve peak performance is a highly non-trivial task Individual settings are not independent; and their consequences depend upon the traffic and application mix, the behaviour of higher-level protocols, the remainder of the network, and the customer's response To complicate matters further, settings which optimise mean achievable bandwidth for large files may be very different from those best for Web-browsing applications; and within a single class the preferred values to minimise mean or median delays may be different from those which minimise different percentiles To study the behaviour of all these, a range of techniques needs to be employed This paper gives examples of analytic, simulation and experimental approaches, and shows how they are all needed for an in-depth understanding

Introducing Home Area Networks

Abstract: What is a home area network and why should we want one? This paper sets out to describe both the developments that have led to the need for a ‘home area network’ within the digital home, and what is meant by a ‘home area network’ and its many variants. It discusses some of the benefits and uses for the home area network and identifies some of the key players in this field.

3G and Beyond — The Applications Generation

Abstract: This paper examines the drivers for the deployment of 3G networks and outlines the applications that will utilise broadband access from mobile terminals. The challenges presented within the telecommunications industry and developments in the supporting technologies surrounding the delivery of mobile broadband services are described. Finally, an overview of the applications currently being delivered on early 3G networks and an assessment of future developments in the mobile arena are presented.

Performance Testing — A Case Study of a Combined Web/Telephony System

Abstract: This paper describes performance testing and how it interfaces with other disciplines within performance engineering. It describes choice of tools and some common pitfalls in setting up a valid performance test. Turning from the general to a case study, a description of performance testing on one product is given, covering both voice and Web application performance testing. Conclusions summarising what makes a successful performance test and its value are drawn.

Standards for Broadband Customer Premises Equipment

Abstract: This paper summarises key BT standards activities in the area of broadband customer premises equipment (CPE), in particular set-top boxes and in-home networking. The paper firstly describes activities in the Digital Video Broadcasting (DVB) Forum on middleware, IP infrastructure, copy protection and in-home wireless networks. It then goes on to despict the CPE activities in the Full-Service VDSL Forum, which is establishing an end-to-end multiservice video delivery platform. These standards will help to drive a range of CPE devices, capable of being connected to BT's broadband networks.

Is the Future Really Always-on? From Always-on Networks to Always-on Sessions

Abstract: For many, the advantages of always-on (AO) are still not clear and the concept can be difficult to understand and distinguish from traditional network connections. How important is the ability to be AO compared to other network characteristics? What will be the quality of the service (speed, availability and reliability) and which services will take full advantage of AO? Is it important to be able to control the information flow? What will be the business model for AO services — would it be cheaper or more expensive than other networks? What are the security and privacy concerns, and are there any social consequences such as less face-to-face contact and user isolation? The paper starts by describing the work done to capture the users' attitudes and expected behaviour towards AO. This includes a review of the initial testing of the AO concept through a number of focus groups and the development of usage scenarios to illustrate the possibilities for AO services. The results from a number of AO user trials are also presented. These user trials were carried out in five different European countries and provide a snapshot of different AO services across Europe. The trials identified a number of technical and operational issues for AO services and the paper makes recommendations for the operation of AO services, and the implications for AO terminals, devices and services. The user trials identified a significant difference between being 'always-on to a network' and being 'always-on to a service' — which seems to be a much more compelling proposition for users. This is further explored in this paper with a description of some ongoing research work investigating this issue through the development of a device-unifying service (DUS) which provides users with a single virtual terminal for all of their devices and access to persistent network-based services, which are 'always-on'. This work was undertaken within EURESCOM, the European Institute for Research and Strategic Studies in Telecommunications, a leading institute for collaborative R&D in telecommunications. It was completed as two separate projects (P1003 'Exploiting the always-on concept', and P1101 'The device-unifying service') with different collaborative partners in each.

Hype and Reality in the Future Home

Abstract: What will stay the same and what will change in homes of the future? This paper tracks and analyses various streams of thought, past and present, looking ahead to emerging technologies which extend and develop our thinking on what might be core to the future home.

Evolution of optical core networks

Abstract: Optical networks have developed rapidly over the last ten years and show every sign of continuing to grow and adapt to the new challenges of supporting more traffic, more reliably and flexibly, at lower cost. We briefly review the developments of the last ten years and then discuss current thinking on how core optical networks will develop into the future, exploring the similarities and differences with the previous generation of technologies. We have attempted to provide a `low-jargon' paper with links to more detailed studies where appropriate.

Middleware for managing a large, heterogeneous programmable network

Abstract: The links between BTexact Technologies and the Department of Computing Science at University College London are becoming increasingly beneficial for the development of the middleware area for the management of programmable networks. This paper describes the work that has been done to date, and outlines the plans for future research.

Capacity Planning for Carrier-scale IP Networks

Abstract: With the growing popularity of Internet protocol (IP)-based networking among business users, the traditional IP ‘best-effort’ service is no longer acceptable. IP network operators need to deliver quality of service in a cost-effective way, and accurate capacity planning will be vital to ensure that the required performance is achieved. This paper highlights some of the challenges in this area and discusses two key activities that usually see a significant contribution from performance engineers — modelling and measurement analysis. Although the focus is on carrier IP networks, many of the issues apply equally to large corporate IP networks.