The Community Authorisation Server (CAS) is an authorisation architecture proposed by the Globus team to manage access to the resources that constitute a Virtual Organisation (VO). These resources are accessed through a restricted delegated X509 proxy managed by an instance of the CAS in accordance with the VO's policy. The Globus middleware is in use by the UK e-Science programme to link computational (and other) resources across the UK to build the Level 2 Grid. The Grid Engineering Task Force (GETF), its members drawn from the Regional e-science and Grid Support Centres funded by the Core programme, is currently undertaking the construction of the UK e-Science Grid.

This JISC (Joint Information Systems Committee) funded project draws together experts from the GETF, other e-science programmes and from the management of Computer Centres to evaluate the technical effectiveness of the CAS architecture for managing distributed resources and its manageability within a distributed VO. It will involve the deployment of the CAS and its integration into Grid resources at the London e-Science Centre (LeSC), E-Science North West (ESNW) and the UK Grid Support Centre (GSC). The ongoing evaluation of this software will feed into the development of:

· A secure web based management tool utilising technology similar to that used within GridSite.

· A CAS enabled web server that will allow policy based access to web sites and the areas within them.

· Deployment of a CAS enabled Gatekeeper and GridFTP server that will allow policy based access to specific computational and storage resources within a site.

The resulting Grid fabric will be available to the wider UK e-science community for extended testing during the project. Software developed during the project will be made available under a recognised open source licence or contributed directly to the Globus project. The evolution of CAS as the UK e-science programme moves from GT2 to GT3 (based upon the Open Grid Services Architecture - OGSA) will also be examined.