Towards the open service web

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Towards the open service web

J Davies, M Potter, M Richardson and S Stinci'c (BT), J Domingue and C Pedrinaci (The Open University), D Fensel (University of Innsbruck, Austria) and R González-Cabero (Atos Origin, Spain)

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SOA4All, a collaborative European research and development project, is pioneering advanced web technology that will allow billions of parties to expose and consume IT services online. Four complementary technical advances are being integrated to create a coherent and domain-independent service delivery platform. Service-oriented architectures and service-orientation principles are being used to support the development of complex services based on distributed and reusable components. Web principles and technology are used to provide an underlying infrastructure that allows the integration of services at a world wide scale. Web 2.0 is used to structure human-machine cooperation in an efficient, user-adapted and cost effective manner. And semantic technology is used to enable service discovery.

Until recently, the internet was a place where a minority of users produced content and most simply consumed it. Now, it is a more thriving and dynamic place. The boundaries between producers and consumers have blurred and the numbers of users and resources available have both increased dramatically. Current estimates suggest the web contains 30 billion static pages and that 10 million new ones are added each day. This transformation has been driven, and illustrated by the success of, Web 2.0. The rapid uptake of this new technology suggests this is not simply a continuation of previous trends but a natural evolution of the web motivated by the increasing importance it plays in our lives. Simultaneously, the software industry has been experiencing a dramatic shift from products to services [1].

From a technical perspective, service-orientation is increasingly being adopted to allow applications to be created flexibly by linking loosely-coupled components, typically over a network. From a business viewpoint, fierce competition between vendors is forcing significant reductions in the price of software products. Companies are being compelled to embrace services to add value to product offerings and establish new revenue streams. Furthermore, the appearance of the internet as a disruptive platform has given rise to new business models such as Software as a Service (SaaS) and advertising-based revenue models (e.g., Google). In the light of these trends, business experts are suggesting that consideration should be given to 'servicising' products to provide added value, and 'productising' services so that they can be delivered more efficiently and at lower costs [1].

Large organisations such as Verizon already have systems based on approximately 1,500 web services [2]. However, the web contains only around 27,000 web services based on the Web Services Definition Language (WSDL) [3]. In consequence, service-oriented architecture (SOA) is largely still an enterprise-specific solution exploited by, and located within, large corporations. Because it minimises costs and maximises the potential market, the fully-automated delivery of services over the web appears to be a potential 'silver bullet' for delivering IT services.

We envisage that the combination of semantic technologies and SOA will lead to the creation of a 'service web'�a web that allows billions of parties to expose and consume billions of services seamlessly and transparently, where all types of stakeholders – from large enterprises to SMEs and singleton end users – engage as peers, consuming and providing services within a network of equals. However, as was highlighted in [4], SOA will not scale without:

- properly incorporating principles that made the web scale to a worldwide communication infrastructure;
- significant mechanisation of service lifecycle activities (which includes location, negotiation, adaptation, composition, invocation and monitoring as well as service interaction requiring data, protocol and process mediation); and
- a balanced integration of services provided by humans and machines.

In a service-oriented world, services must be discovered and selected based on requirements, then be orchestrated and adapted or integrated. If a web interconnecting billions of services is to be realised, the way this is done must clearly be both scalable and manageable.

In this paper, we present the principles and rationale behind the EU Seventh Framework project 'Service Oriented Architecture for All' (SOA4All [5]) based upon the integration of SOA, semantic, web and Web 2.0 technologies. After describing how these 'technological pillars' will be integrated in SOA4All, we indicate how our approach would be instantiated within a telecoms application.

At the heart of our approach are SOA and service-orientation that embody a number of key principles [4], which we describe below.

- Standardised service contract principle. In order to make the description of service capabilities understandable to any interested party, the properties of a service – the service contract – should be compliant with some design standard. The service contract may include information to identify the services such as a URL, name, textual description; functional properties, such as the type of the input/output parameters or the interaction model; and non-functional properties, such as Quality of Service (QoS), the location of the service and security constraints. Standardisation supports the global interpretability of services, resulting in an increase in the predictability of the service behaviour. The ability to predict the future behaviour of a service is a key mechanism to achieve scalability, since it facilitates the evaluation of the necessary computational resources required to enact a specific service. This mechanism enables the intelligent provisioning of resources.
- Abstraction principle. The abstraction principle dictates that the details of software artefacts that are not required for effective use should be hidden. Therefore all the information necessary to invoke the service is contained in the service contract. Equally, all the knowledge of the underlying logic and platform technology should be buried completely. The abstraction principle enables replaceability which, when combined with fault isolation and fault recovery as outlined in [6], enhances scalability.
- Reusability principle. The reusability principle states that the functionality provided by services must be as domain- and context-independent as feasible, facilitating reuse [7]. As a direct consequence of the application of this principle, the logic of a service should be highly generic – that is, independent from its original usage scenario. The reusability principle is a key enabler for SOA infrastructures, since it makes possible the creation of huge libraries of domain-independent services that leverage the construction of new complex context-dependent services.
- Autonomy principle. The autonomy principle states that services should be able to carry out their processes independently from outside influences. The only way to affect the results of a service should be through the modification of the input parameters as specified in the service contract. Service autonomy increases reliability and, more importantly, predictability and fault isolation. As set out in [6], this leads to improved system scalability.
- Statelessness principle. The statelessness principle dictates that services should minimise resource consumption by deferring the management of state information when necessary [7]. This notion of statelessness has been taken to the extreme in the REST architectural style [8], which has also been successfully applied to SOA in recent years. Because state maintenance is one of the most resource consuming tasks in computer science, conformance with the statelessness principle is vital if the entire SOA infrastructure is to be scalable.
- Discoverability principle. The discoverability principle states that, to enable discovery by interested parties, services should be annotated with metadata. This principle is closely related to the standardised service contract principle. - Composability principle. The composability principle requires services to be identified as effective composition participants, regardless of the size and complexity of the composition [7]. From a bottom-up perspective, this allows simpler services to be combined into larger services (c.f. reusability). Looked at topdown, service composition is an effective way to tackle the complexity of certain types of processes (c.f. abstraction). Because the ability to create new services easily is a key pre-requisite for the widespread take up of SOA, the composability principle is a core element within the definition of a service web.

Despite the original aim to support inter-organisational processes on the basis of SOA, it still remains almost exclusively an intra-organisational solution. To support the service web, we believe the principles underlying SOA must be revisited and extended with others coming from the web, semantic technology and Web 2.0 systems. We consider each of these in turn in the next three sections.

The service web will lead to a global, dynamicallychanging environment of services accessible for thirdparty usage. Services will undergo many changes within this environment, as resources currently do on the web, and the rate of churn will be very high. Users and resources will appear, disappear, and change location. Resources that initially are available free will transform to pay-peruse and vice versa. And services may occasionally be blocked, out of service, or inspected for antitrust violations. As a result, we believe that the transformation of SOA into an architecture comprised of billion of services requires the embodiment of the principles which made the web such a successful platform for the worldwide sharing of content.

Among the main principles underlying the web, its distributed and open nature is most relevant. The web is essentially a collection of distributed resources which, however, transparently appears to the user as a single entity where anybody can provide and consume resources. Distribution enables scalability but, when it comes to supporting the execution of processes, the absence of central control over many of the resources and services involved means other mechanisms must be provided to cope with changing conditions. Research in serviceoriented computing already recognises the need for dynamic and adaptive processes within enterprises [9]. The service web will exacerbate this to a point where the existence of adequate means for self-configuring, selfadapting or self-healing processes will determine its success. In addition, aspects like the discovery and composition of services and the distributed and open nature of the service web will make it a very valuable yet technically challenging environment.

Another principle underlying the web is the use of a vendor-neutral interoperability platform that supports, and is based on, the integration of heterogeneous and proprietary solutions. A web of billions of services will require an advanced infrastructure that properly supports the integration of data and processes independently of their format, protocol or location. In fact, we foresee the creation of constellations of service ecosystems that span institutions, communicating seamlessly using the service web as a common interoperability platform.

Finally, a key feature of the web lies in the central role that users play. The ability to maintain this role in the service web will determine the market for services, which will in turn affect the uptake of service technologies on a web scale. For users to continue to play a central role as the service web evolves and grows, simple yet fully-fledged and customisable solutions must be created.

Standards for describing web services currently use syntactic (XML-based) notations such as WSDL. These descriptions are not amenable to applying automated reasoning, so specialist workers must be involved throughout the web service lifecycle. This causes numerous problems, the most significant of which is the lack of scalability. It simply isn't possible to maintain millions, let alone billions, of services to cope with environmental and context changes, discover new services, compose them or support their adaptation at runtime through human effort alone. Researchers studying the semantic web, semantic web services and more traditional artificial intelligence have shown it is possible to automate some of these tasks to a significant extent (see, for instance, work in OWL-S [10], WSMO [11], WSDL-S [12], semantic execution environments [13,14] or planning [15]). Based on their findings, we decided to use semantic technologies as a core pillar of the service web.

By providing semantic descriptions of service interfaces and capabilities, the way is paved for simplifying and further automating the discovery of suitable services. In particular, services can be discovered based on the capabilities they offer rather than the low-level messages exchanged. Our approach to discovering suitable services is based on the notion of goal set out in WSMO. On the one hand, goals provide means for users to model explicitly their requirements (what to do); on the other, they serve as a natural abstraction over web services (how to do it). The notion of goals therefore enables the reusability of existing services while reducing the complexity for managing billions of services by providing additional layers of abstraction for guiding the discovery process [2].

This very distinction between goals and web services also enables what is usually referred to as late binding – that is, service selection at run-time [13,14] – which has proven a useful approach for the management and execution of services [16]. From the management perspective, specifying processes in terms of goals provides further robustness and maintainability to the process models avoiding the creation of 'spaghetti solutions' that deal with the specifics of different service provider's implementations and using instead a single entry point. From an execution perspective, the infrastructure is given the possibility to choose the 'best' service taking into account contextual factors.

To achieve the level of flexibility required for the service web, we decided to extend the heuristic classification-based engine we use to dynamically select trusted services [17] to support more general contextual data such as location and pricing models. To cope with the high dynamism and unreliability of the web – that services may disappear, change their pricing model and so on – additional adaptive capabilities are required. To deal with changing conditions while also ensuring that service-level agreements are met, processes must be self-optimising. And to deal with unreliable services, they must also be self-repairing. To meet these requirements, we make use of:

- semantic descriptions of functional and non-functional properties of services;
- parametric design techniques [18] for supporting the (re)configuration of services based on contextual factors; and
- event-based opportunistic reasoning techniques based on the use of semantic spaces [19,20].

By reducing the complexity for creating new services out of existing ones, full support for the creation of services within the service web will play a very important role in the uptake of service technologies. We have therefore decided to approach the creation of services through both manual and (semi-) automated processes. As is explained in more detail in the next section, this provides better support to users creating services. The (semi-) automated creation of atomic services will also be supported by intelligent recommenders that analyse service documentations and suggest semantic annotations. Furthermore, to ensure scalability, the creation of composite services will be supported by applying parametric design-over-process templates. This avoids the computational complexity of planning techniques [21].

Finally, throughout their lifecycle, services will benefit from the presence of formal semantic descriptions that enhance interoperability between humans and machines as well as between machines and other machines. Higher-level conceptual descriptions will bridge the gap between the user and the service descriptions and support the integration of information through semantic web technologies such as RDF(S) [22].

The adoption of Web 2.0 technologies and principles within the service web will accelerate the take-up of service technologies and make it easier to integrate the user within the overall architecture as an additional and extremely valuable source of information and computational power. To achieve this goal, the semantics we use are kept lightweight. User interfaces are enhanced with recommender systems that make them more intuitive to use, and the distinction between providers and consumers is blurred.

        Figure 1. Protocol usage of published web APIs (reproduced from [25])

The use of lightweight semantic descriptions reduces computational complexity, making it easier for users to achieve their tasks. In particular, we use WSMO-Lite [23] and MicroWSMO [24] for the annotation of WSDL and RESTful web services. These semantic descriptions will allow efficient and scalable reasoning about services and will reduce the complexity for users. Note that, in this sense, the project intends to be protocol-neutral, an important feature given the split between RESTful and WSDL-based web services. Figure 1 shows the usage of each as reported by ProgrammableWeb [25], a website that maintains a comprehensive directory of web Application Programming Interfaces (APIs) [26] and the protocol(s) they support.

Users will be given the means to create lightweight service annotations by making use of recommender systems, but also through intuitive user interfaces such as mash-ups or pipes. Currently applied to data, these Web 2.0 solutions will be adapted to support the definition of simple service compositions and their publication. Through this simple mechanism, people will co-operate in building online communities around services. Simultaneously, such services will interoperate with one another to offer more sophisticated functionalities to the users in a largely automated way. Services will be combined in increasingly complex mash-ups that offer functions to support users both at home and work, helping them to perform their daily activities. This approach will blur the distinction between service consumers and providers, shifting the paradigm to one where users are active and are therefore contributing to the service web, rather than just being consumers of services. By incorporating human interaction and cooperation in a comprehensive fashion, tasks such as service ranking and mediation can be addressed that would otherwise be computationally expensive or even infeasible. In our view, the overall quality of the services available to the end-user can be increased significantly if it is transparent whether the 'engine' that abstracts services is completed by humans or machines.

Figure 2 summarises the impact of the four technological pillars discussed above on the service web of the future. By combining the semantic and social dimensions, Web 2.0 and semantic technology, we arrive at Web 3.0. By combining semantic technology and web services, we create semantic web services. And by combining Web 2.0 and web services, we create the possibility of service communities. Finally, as shown in figure 2, when we combine all the advantages and enhancements offered by the four pillars, we arrive at the service web.

        Figure 2. Service web technological pillars

In this section, we will look at the potential impact of the emerging service web on the telecommunications sector. We start by setting out the business background, showing how the drive to an open service ecosystem is increasingly seen as inevitable and the implications for the telecommunications sector and beyond. We then explain the potential benefits gained by the deployment of semantic and Web 2.0 technologies in a specific telecommunications public SOA environment, BT's Ribbit services platform.

6.1 Business background and the drive to open service ecosystems
With the increasing tendency of service providers of all types to publish services via the web and the emergence of Web 2.0 technologies, traditional telecoms companies (telcos) are being forced to evolve. Indeed, figure 3 reveals that the telecommunications sector is among the leading areas for publication of functionality via the web. The key technological trends which demand telcos' immediate response come from Web 2.0 developments. Webcos – companies adopting Web 2.0 principles in their business models – are able to respond to changing demands and expectations in the marketplace by innovating at multiple levels. Their products are distinguished by the following key characteristics:

- Web as platform: The platform is no longer a specific server or application, but exists on the web ('in the cloud') and is characterised by the publication of capabilities rather than vertical applications (for example, the exposure by Google and Amazon of APIs via the web).
- Architecture of participation (harness collective intelligence): designed to encourage users to take part, to share, to customise, to connect and even to participate in future product design (for example, user generated content – Flickr, YouTube, Delicious, mySpace, eBay, Amazon, social networks and user participative sites such as Wikis, blogs, Amazon reviews). The wisdom of crowds is a phrase used to refer to the harnessing of large numbers of end-user views and insights via these technologies.
- Mashups: as mentioned in the previous section, lightweight and rapid service/product composition in an open service ecosystem, leading to a larger number of applications developed more quickly and able to serve niche markets.
- Long tail: monetising the demand from the large number of highly diverse potential customers with nontypical requirements. Traditionally, telcos have focussed their efforts on a much smaller number of products and services addressing a larger market. In the Web 2.0 world, telcos can no longer ignore the revenues generated from the long-tail.

        Figure 3. Top 15 categories of published web APIs (reproduced from [25])

Ribbit [25], a wholly-owned US-based BT subsidiary and a voice-oriented web company ('webco'), currently allows developers to consume voice services accessible via Adobe's Flex and Flash. The services that are exposed at the moment include voice calls, call routing, call management, thirdparty call control, voice and text messaging, speech-to-text, VoIP and contact management, with more to come in the near future. Currently, users require detailed technical knowledge of the Flex and Flash programming languages to be able to access, combine and use Ribbit's web services. In the SOA4All project, the use of contextual knowledge will support both the composition and provisioning of services in a customised manner. Contextual knowledge, which we discuss in further detail in section 6.2, includes, for example, knowledge about end-users and their preferences as well as about the previous experience of other users with respect to use of particular services. Using automation, we plan to shield service users from the complexities of creating such knowledge. BT will also take advantage of semantic descriptions of services in building (semi-) automated provisioning, composition, consumption and monitoring tools. The next-generation platform we envisage will also enable inclusion of third party services. In addition, it will address several key issues for BT's transformation, including:

- reducing time to market;
- enabling third-party services to be integrated into BT's portfolio;
- increasing so-called 'new wave' revenues from networked IT services; and
- extending BT's SOA to the public web.

The possibility of increased competition from the 'Over The Top' (OTT) service providers – service and content providers that don't own the network they use – highlights a risk that telcos could become 'disintermediated' from the digital supply chain, consigned to the role of a commodity 'dumb' pipe provider. Webcos typically use advertisingbased business models, whereas telcos collect revenues through usage-based billing. As these two sectors converge, the challenge for telcos is to reconcile the two different business models, finding ways to generate revenue from advertising, while continuing to offer billable services where appropriate. Finally, other changes are apparent such as the rise in virtual social networking, the roll-out of alternative access networks such as WiMax and the emergence of enterprise mashups that use Web 2.0-style applications alongside more traditional IT assets.

Considering all these aspects, by appropriately positioning themselves in the Web 2.0 world, telcos will continue to evolve and transform themselves from mere 'dumb' pipe providers to providers of 'smart' pipes (connections backed by QoS guarantees and service level agreements), platforms that support an open service ecosystem and a range of telco and third-party applications that run on such platforms. Telcos will not only need to create new services to address the needs of the long tail, but also allow third-party service providers to make use of telcos' underutilised operations and business support systems capabilities to create new service offerings, thereby creating new revenue streams.

Figure 4 shows the long tail, representing untapped new business revenues, and the short head, representing the conventional telco business revenues. Figure 5 gives a high level view of the kind of platform and tools a telco might offer to allow telco and other services to be published and combined into applications. It can be seen that new growth opportunities will arise from externalising current capabilities, allowing both the telco itself and third-party developers to address long tail demand.

        Figure 4. Leveraging the long tail

        Figure 5. Open service web platform and tools

Telcos have historically been used to controlling the entire value chain from core network to end user. As discussed above, the long tail business model involves letting the market innovate, by using third-party developers to define how new services will be generated. Because this involves opening up the network, some loss of control is inevitable. In the future, the technologies employed will be telecom web services, representing an amalgam of telco services and internet services, enabling the telco to access long tail revenues via innovative niche applications from third party developers: the telco is taking the role of an aggregator.

6.2 Application of SOA4All technology
The partners in SOA4All are investigating how BT – and, potentially, other telcos – can apply the technology being developed in the project's various core research areas to deliver next-generation web-based open services platforms. Below we describe the application of each technology area in turn.

6.2.1 Web 2.0
User-generated and maintained communities are an essential part of the case study, as well as encouraging ease of use and a low barrier to entry in utilising SOA. SOA4All technology based on Web 2.0 principles helps encourage this, specifically to:

- encourage users to work together to create new and innovative uses for BT services by providing an appropriate Web 2.0 community environment;
- provide facilities for the user to share information about services and applications;
- allow users to tag, rate and comment on services for improved service discovery; and
- improve the usability of SOA, and facilitate the creation and management of new composed services, in a lightweight manner, with a low barrier to entry.

Related to the availability of Web 2.0-style tools for developers and users, the use of contextual knowledge will be key in supporting both the customised discovery and composition of services. The complexity underlying this will, however, be automated, so the process will remain hidden from the service user.

Service composition will use contextual knowledge about both the user domain, (for example, knowing the current user is an ISP targeting rural areas) and community knowledge (for example, knowledge of services tending to be used by similar ISPs) to suggest and customise solutions based on prior experience. As a result, the user will obtain more specific and more adapted proposals, which will simplify the selection of suitable services. This can be achieved by pre-defining each constituent service with a number of options, by parameterising certain functionality, and by providing a context-adapted service discovery and selection process according to pre-identified context dimensions.

Service provisioning will also be enhanced by the use of contextual knowledge. This will be achieved at run-time by integrating execution information, together with contextual knowledge such as user preferences and trust relationships (for example, which service providers does a given end-user trust). To do this, the service execution platform will integrate the information populated by the monitoring infrastructure with the contextual knowledge base, and will seamlessly invoke the context parameterisation engine as the need arises.

6.2.2 Semantics
BT will take advantage of the semantically-enabled improvements in provisioning, consumption and monitoring tools that are offered by SOA4All technology. Semantic descriptions for web services and goals will be built by BT and non-BT users in a straightforward way using purpose-built tools, allowing them to make available their services, or to discover and use the services of others, more efficiently. Similarly, semantics will also be important to enable new composition tools that will enable the creation of more complex services at lower cost.

Ontologies and semantic descriptions will form the basis for data, process and service representation in SOA4All. In the context of applying SOA4All technology to future web-based telco platforms, telecommunications domain ontologies will also be used . One example is NGOSS (Next Generation Operations Systems and Software), an industry-wide specification developed by the TeleManagement Forum [29] the purpose of which is to organise and guide the design and development of next generation operation systems in the telco domain.

NGOSS contains a set of frameworks, high-level architecture and methodology. It consists of four frameworks related to the different levels of looking at business which are:

- the business process framework (Enhanced Telecom Operations Map – eTOM)
- the enterprise-wide information framework (Shared Information and Data model – SID)
- the applications framework (Telecom Applications Map – TAM )
- the systems Integration framework (Technology Neutral Architecture – TNA)

Ontologies have been developed that capture telecommunication sector knowledge from NGOSS's standards. The SID model contains domain concepts related to market, product portfolio, customer, services, resources, the enterprise and supplier/partner, as well as common business terms called Core Business Entities (CBE) which are captured in the CBE Ontology (CBEO). The eTOM map defines a set of functional areas which serves as a reference classification for the business goals a process fulfils and which are captured in the business goals ontologies (BGO). The TAM map defines the typical IT systems map of telecommunication companies, and serves as a reference classification for a company's services map.

6.2.3 Services
As mentioned above, BT's current offering consists of Ribbit's services including voice calls, call routing, call management, third-party call control, voice and text messaging, speechto- text, Voice over Instant Messaging (VoIM) and contact management, with more to follow shortly. As more services are made available, they will be included on the next generation platform.

In addition, there are also other business-to-business gateways and APIs that BT uses for interaction with its customers and suppliers, such as broadband provisioning [25], repair and diagnostic services. SOA4All technology also has the capability to describe these services in the same semantic framework (see, for example, [31]), allowing them to be combined with Ribbit services.

The third and final class of services are third-party services. One of the main aims of the case study is to promote the uptake of Ribbit by offering tools to encourage innovation in using and combining BT's services. SOA4All technology will make it easier not only to consume BT's services but also to combine them with other people's services to make new and interesting applications.

SOA4All will help to realise a world where a massive number of parties expose and consume services via advanced web technology. The outcome of the project will be a comprehensive framework and software infrastructure which will integrate complementary advances into a coherent and domain-independent worldwide service delivery platform. To achieve such a scalable and widely adopted infrastructure and framework, SOA4All stands on four main principles comprising: SOA, semantics, the web and Web 2.0. Our technologies will be proven in a number of real-world applications including the telco scenario outlined above.

From our point of view, we believe that the successful integration of semantic web and service-oriented technologies will form the main pillar of the software architecture of the next generation of computing infrastructure. We envision a transformation of the web from a web of static data to a global computational resource that truly meets the needs of its billions of users. Computing and programming will be positioned within a services layer thus putting problem solving in the hands of end-users through a truly balanced, cooperative approach.

This work has been partially supported by the EU co-funded IST project SOA4All (FP7-215219). We thank Jean See, Manooch Azmoodeh and Rosita Venousiou for their input.

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John Davies leads BT's next generation web research group and is Chief Scientist, Semantic Technology in BT's Centre for Information Systems and Security Research. His interests include the application of semantic and Web 2.0 technologies to business intelligence, information integration, service-oriented environments and knowledge management. John has written and edited many papers and books on semantic technology and its applications, web-based information management and knowledge management. Currently coorganiser of the European Semantic Web Conference series and chairman of the European Semantic Technology Conference, he has served on the program committees of many conferences in related areas. John is a Fellow of the British Computer Society and a Chartered Engineer.

Sandra Stinci'c is a senior researcher in BT's next generation web research group. After graduating from the University of Zagreb's Faculty of Electrical Engineering and Computing in 2005, she joined BT as a developer of semantic web applications. Sandra has been involved in several projects related to the semantic web and web services, including the EU 6th framework projects 'Data Information and Process Integration with Semantic Web Services' and 'Semantic Knowledge Technologies'. She is currently involved in the EU Seventh Framework project 'Service Oriented Architecture for All', SOA4ALL, where her work is focused on semantic technology and its application in telecommunications.

Morgan Potter is a principal research analyst in BT's insights research centre. Before taking his current position, he was engaged in the development of IP multimedia standards and technology – areas in which he holds two patents. In 2000, he moved to another of BT's research teams to develop his interest in strategic management. A member of the Institution of Engineering and Technology and a Chartered Engineer, Morgan holds a first degree in Electronic Engineering and two Masters degrees in Business Administration, and is about to complete a Doctorate in Business Administration at Aston University Business School covering the enactment of regulated strategic environments. He is a member of the British Academy of Management and the Strategic Management Society.

Prof John Domingue is deputy director of the Knowledge Media Institute at The Open University and the President of STI International, a semantics-focused networking organisation with just under 40 members. The author of more than 100 articles on artificial intelligence and the web, his current work is focused on the use of semantic technology to automate the management, development and use of web services. John serves as the Scientific Director of SUPER and sits on the Executive Board of SOA4All. Each is a large EU project involving almost 20 partners. He is chair of the steering committee for the European Semantic Web Conference series, chair of the Future Internet Symposium series and co-chair of the OASIS Technical Committee on Semantic Execution Environments and serves on the editorial boards for the International Journal of Human Computer Interaction, the Journal of Web Semantics and the Applied Ontology Journal. He also coordinates the Services Future Internet Working Group allied to the Software and Services Unit in Brussels.

Marc Richardson is a senior researcher in BT's next generation web research group. He joined BT in 2001 as a developer of knowledge management applications and was involved in the formation of Infonic, a knowledge management company based on BT's research. His work is currently focused on research of the semantic web and its application in telecommunications. Having worked on a number of projects related to the semantic web, web services and service orientated architectures, he is currently contributing to the EU 7th framework project, SOA4ALL.

Carlos Pedrinaci is a research fellow at The Open University's knowledge media institute. With a PhD in artificial intelligence from the University of the Basque Country in Spain, his research interests include semantic web services, knowledge based systems and business process analysis. Allied to these interests, he has contributed to European projects researching e-business, semantic web services and service-oriented architectures including OBELIX, DIP, SUPER and SOA4All. As a member of the OASIS SEE TC, the WSMO Working Group, the CMS Working Group and the W3C SAWSDL Working Group, Carlos is actively involved in the standardisation of semantic web services technologies.

Dieter Fensel is the scientific director of the Semantic Technology Institute Innsbruck at the University of Innsbruck, Austria, and is a leading expert in the fields of semantic web, semantic web services, and semanticallyenabled service-oriented architectures. Having graduated in Social Science (Free University of Berlin) and Computer Science (Technical University of Berlin) in 1989, he obtained his PhD in Economic Science from the University of Karlsruhe in 1993. Dieter has published more than 200 papers in his fields of interest and has co-organised more than 200 academic workshops and conferences.

Rafael Gonzalez Cabero is a member of the Ontology Engineering Group at the Polytechnic University of Madrid, where he is finishing a PhD on semantic services and event-driven architectures. An active participant in semantic-related EU projects and networks of excellence including OntoWeb, Esperonto, Knowledge Web, OntoGrid, LUISA and SOA4All, he is an expert in semantic web representation languages, semantic web services and the semantic grid. His papers have been published in several research journals and in the proceedings of key international conferences.

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