a Frame Work Of Web science

Introduction

The World Wide Web is a technology that is only a few years old, yet its growth, and its effect on the society within which it is embedded, have been astonishing. Its inception was in support of the information requirements of research into high energy physics. It has spread inexorably into other scientific disciplines, academe in general, commerce, entertainment, politics and almost anywhere where communication serves a purpose. But neither the Web nor the world is static. The Web evolves in response to various pressures from science, commerce, the public and politics. For instance, the growth of e-science has created a need to integrat large quantities of diverse and heterogeneous data; e-government and e-commerce also demand more effective use of information. We need to understand these evolutionary and developmental forces. Without such an appreciation opportunities for adding value to the Web by facilitating more communicative and representational possibilities may be missed. But development is not the whole of the story. Though multi-faceted and extensible, the Web is based on a set of architectural principles which need to be respected. Furthermore, the Web is a social technology that thrives on growth and therefore needs to be trusted by an expanding user base – trustworthiness, personal control over information, and respect for the rights and preferences of others are all important aspects of the Web.

A research agenda that can help identify what needs to stay fixed and where change can be profitable is imperative. This is the aim of Web Science, which aims to map how decentralized information structures can serve these scientific, representational and communicational requirements, and to produce designs and design principles governing such structures. ‘Web Science’ is a deliberately ambiguous phrase. Physical science is an analytic discipline that aims to find laws that generate or explain observed phenomena; computer science is predominantly (though not exclusively) synthetic, in that formalisms and algorithms are created in order to support particular desired behaviour. And of course the Web’s use in communication is part of a wider system of human interaction governed by conventions and laws. The various levels at whichWeb  technology interacts with human society mean that interdisciplinarity is a firm requirement of Web Science.

Such an interdisciplinary research agenda, able to drive Web development in socially and scientifically useful ways, is not yet visible and needs to be created. To that end, in September 2005 a Web Science Workshop was convened in London, UK (details of the contributors to the Workshop are given in the Acknowledgements). The workshop examined a number of issues, including:

• Emerging trends on the Web.

• Challenges to understanding and guiding the development of

the Web.

• Structuring research to support the exploitation of opportunities

created by (inter alia) ubiquity, mobility, new media

and the increasing amount of data available online.

• Ensuring important social properties such as privacy are

respected.

• Identifying and preserving the essential invariants of theWeb

experience.

This text grew out of the Web Science Workshop, and it attempts to summarise, expand and comment on the debates. That an interdisciplinary approach was required was agreed by all, encompassing computer science and engineering, the physical and mathematical sciences,

social science and policymaking.

The Web and its Science

We may paraphrase Web Science as the science of the Web. We will review the basic architectural principles of the Web, designed to support growth and the social values of information-sharing and trustworthy behaviour in Section 2.1. Section 2.2 will then offer a few methodological reflections on the scientific investigation of the Web.

2.1 Web architecture

The architecture of the Web exploits simple technologies which connect efficiently, to enable an information space that is highly flexible and usable, and which, most importantly, scales. The Web is already an impressive platform upon which thousands of flowers have bloomed, and the hope is it can grow further, encompassing more languages, more media and more activities, hosting more information, as well as providing the tools and methods for interrogating the data that is out there.

The Web is a space in which resources are identified by Uniform Resource Identifiers (URIs – [33]). There are protocols to support interaction between agents, and formats to represent the information resources. These are the basic ingredients of the Web. On their design depends the utility and efficiency of Web interaction, and that design depends in turn on a number of principles, some of which were part of the original conception, while others had to be learned from experience.

Identification of resources is essential in order to be able to share information about them, reason about them, modify or exchange them. Such resources may be anything that can be linked to or spoken of; many resources are purely information, but others not. Furthermore, not all resources are on the Web, in that they may be identifiable from the Web, but may not be retrievable from it.

For these reasoning and referring functions to happen on the global scale, an identification system is required to provide a single global standard; URIs provide that system. It would be possible for alternative systems to URIs to be developed, but the added value of a single global system of identifiers, allowing linking, bookmarking and other functions across heterogeneous applications, is high. Resources have URIs associated with them, and each URI ideally identifies a single resource in a context-independent manner. These principles of relationship between URIs and resources are desirable but not strictly enforceable; the cost of failing to associate a URI with a resource is the inability to refer to it, while the cost of assigning two resources to a URI will be error, as data about one resource gets applied to the other. URIs also connect the Web with the offline social world, in that they require institutions. They fall under particular defined schemes, of which perhaps the most commonly understood are HTTP, FTP and mailto; such schemes are registered with the Internet Assigned Numbers Authority (IANA – http://www.iana.org/assignments/urischemes).

So if we take HTTP as an example, HTTP URIs are owned and disbursed by people or organisations; and hence can be allocated responsibly or irresponsibly. For instance, an HTTP URI should refer to a single resource, and be allocated to a single owner. It is also desirable for such a URI to refer to its resource permanently, and not change its reference over time (see Section 5.4.6 below). Communication over the Web involves the exchange of messages which may contain data or metadata about a resource. What accessing an information resource entails varies from context to context, but perhaps the most common experience is receiving a

representation of the (state of the) resource on a browser. It certainly need not be the case that dereferencing a URI automatically leads to

the agent getting privileged access to a resource. It may be that no representation of the resource is available, or that access to a resource is secure (e.g. password controlled), but it should be possible to refer to a resource using its URI without exposing that resource to public

view. The development of the Web as a space, rather than a large and complex notice board, follows from the ability of agents to use interactions to alter the states of resources, and to incur obligations and responsibilities. Retrieving a representation is an example of a so-called

safe interaction where no alteration occurs, while posting to a list is an unsafe interaction where resources’ states may be altered. Note that the universal nature of URIs helps the identification and tracking of obligations incurred online through unsafe interactions. Not all URIs are intended to provide access to representations of the resources they identify. For instance, the mailto: scheme identifies resources that are reached using Internet mail (e.g.mailto:romeo@example.edu identifies a particular mailbox), but those resources aren’t recoverable from the URI in the same way as a webpage is. Rather, the URI is used to direct mail to that particular mailbox, or alternatively to find mail from it.