Conclusion

The left-hand side shows the selection of a particular course-related group (all those involved in Forced Migration studies) which is available from automated feeds from student records data. On the right-hand side are listed the different kinds of access to resources. The owner of a resource can thus choose which groups can have 'see' and 'view' access to read the contents. The system might be further developed so that members of groups with 'post' rights are able to comment on a blog, and so on. For blogs to be restricted in this way means that most people will come to the blog through the learning context of the VLE. A very basic proof of concept was achieved, but the technical solution is not appropriate for a production service.

Thus conceived, the blog server is used to store all the blog entries. At the same time, Bodington VLE users make use of access control systems to set who can access the blog via a display of an RSS/Atom feed. When authorised users view this resource, Bodington downloads the RSS and renders it to HTML, sending the output to the client (browser). In this scenario there is implicit co-ordination between the blog server and VLE: when a user is in the VLE and attempts to access a private blog the VLE does the authorization and Pebble has to trust the VLE completely.

This is an illustration of the general problem of secondary authentication, the same issue commonly encountered in portals where there is the need for trust between machines. It soon becomes evident that interoperating systems need an infrastructure in which authentication and authorisation services stand outside any particular application and are readily accessible by the various applications. Problems like these have led to the development of component-based frameworks and Service Oriented Architectures, an approach that is being actively promoted by JISC in their E-Learning Framework (ELF) [17]. Demonstrators, toolkits and reference models are being developed for ELF against which existing systems may evolve from monolithic structures to more reusable component-based services. One of the demonstrator projects is BEWT [18], which will develop an IMS Enterprise service for Bodington Authorisation, the kind of service that should lead to richer communication between blogs and learning environments.