An Agent Architecture for a Virtual Research Digital Library
Department of Organization and Enterprise Management (Information Systems and Management Group - CENEGE),
Universidade Aberta (Portuguese Open University), Rua Fernão Lopes, 9, 1-Esq, 1000 Lisbon, Portugal
This paper argues that agents can help to structure and implement a digital library. An example of this is the Virtual Research Digital Library, which is presented in detail: architecture of agents with each agent's role explained. This paper also shows how the agents can contribute and play an active role in the electronic publishing process and how the whole-proposed architecture sets an electronic commerce framework between publishers, authors and consumers. The traditional vs. electronic publishing processes are presented in detail to show the new approaches and agents roles and the benefits within the electronic commerce framework are described for the participating parties.
Keywords: Digital Libraries; Software Agents; Electronic Commerce; Electronic Publishing
This paper presents a Virtual Research Digital Library (VRDL) based on a architecture of agents and also shows the role of agents in the electronic publishing process.
It starts by explaining the traditional publication process phases and key players versus the electronic publishing process phases. Then it explains digital libraries role within the electronic publication environment and justifies the use of agents to define a digital library architecture. It also explains the important role that agents can play in the electronic publishing process. A VRDL architecture is presented with the agent's roles described and advantages exposed. The paper also shows the electronic commerce framework that the VRDL creates.
2. From traditional publication to electronic publishing
In a traditionally publication process (i.e. of a paper in a journal) there are four phases  (see Figure 1):
Figure 1 - Traditional publication phases of a scientific paper
In a electronic publishing process (i.e. of a paper) there are up to four phases (see Figure 2):
Figure 2 - Phases of electronic publishing of a scientific paper
3. Agents role in electronic publishing and digital libraries
From what has just been described regarding traditional publication's transition to electronic publishing, how important are digital libraries and what role can agents play within them and within electronic publishing?
Digital libraries are a set of well-organised technologies and, above all, a very important source of structured, well-organised and well-stored information. They are gaining increased importance with the exponential Internet growth mainly because they help to structure, organise, and store important information.
Agents can effectively host an architecture to support a digital library and be present in the electronic publishing process, helping to bridge the gap between information producers (i.e. authors), publishers and information consumers.
Agent's application to digital libraries is not an entirely new concept. In fact there have been several initiatives that use agents in digital libraries, being the most relevant the following:
4. VRDL - Architecture proposal
In this architecture, which basically is an information distributed service over the Internet, each type of agent has a specific role. Figure 3 shows the VRDL architecture.
Figure 3 - VRDL architecture
The proposed architecture is composed of eight different types of agents. Here is a description of the types of agents and their roles (as described in ):
The proposed architecture is currently being developed with the ZEUS agent system from British Telecom. This agent development environment has a very important characteristic: The agents are produced in the Java language, which is very important for platform independence and communication between all party systems.
5. Advantages of the VRDL
In its essence, The VRDL acts as a distributed Electronic Copyright Management System (ECMS). Advantages of ECMS  that are present in the proposed digital library:
Moreover the VRDL makes it possible for every party in the process to have greater and direct control of its role and responsibility and thus being more efficient.
6. Electronic commerce framework
Agents in digital libraries provide an effective electronic commerce framework where key players pursue their goals through the aid of the agent architecture and communicate fast and efficiently between each other. Particularly in the proposed VRDL, there are several benefits for each participating party from this framework:
In this paper, it was presented the traditional publication's transition to electronic publishing and the importance of digital libraries. It was argued that agents where suited to host such an architecture and could play an important role within this library and within electronic publishing.
The VRDL architecture of agents was detailed with its eight agent types presented and briefly described. It was also argued that this architecture of a digital library is well suited for an effective electronic framework between the main players: Publishers, authors and consumers.
 Atkins, D. et al. (1996, May). Toward Inquiry-Based Education Through Interacting Software Agents. IEEE Computer [Online], 29 (5), pp. 69-76. Available: http://computer.org/computer/dli/r50069/r50069.htm [2000, March 30]
 Barth, A. ed. et al. (1998). Digital Libraries in Computer Science: The MeDoc Approach, Springer
 Denning, P., Rous, B. (1995).The ACM Electronic Publishing Plan, Communications of the ACM, Vol. 38, N. 4, pp 97-103. Available: http://www.acm.org/pubs/epub_plan.html [2000, March 30]
 Derbyshire, D. et al. (1997). Agent-Based Digital Libraries: Driving the Information Economy. In Proceedings of the Sixth IEEE Workshops on Enabling Technologies: Infrastructure for Collaborative Enterprises, pp. 82-86
 Isaias, P. (1999, October 24-30). Agents in Digital Libraries and Electronic Publication: An Architecture Proposal. In Proceedings of WebNet 99 - World Conference on the WWW and Internet, pp. 1542-1543
 Isaias, P. (1999, June 22). Electronic Copyright Management Systems: aspects to consider. Ariadne magazine [online], Issue 20, 24 paragraphs. Available: http://www.ariadne.ac.uk/issue20/ecms/ [2000, March 30]
Pedro Isaias is assistant professor in Universidade Aberta (Portuguese Open University). He is a researcher in the digital library field and has extensive experience in European projects in this area. He is a PhD Candidate in Universidade Nova de Lisboa (New University of Lisbon).