Responsiveness on the Interactive Grid

The Grid vision promises the secure and dynamic sharing of heterogeneous resources across the Internet. To date the emphasis has been on supercomputing scenarios where a relatively long running job is submitted to the Grid, requiring little interaction with the end user. More recently, with the emerging aspirations of Grid aficionados to use it for a much wider range of purposes - e-commerce and inter-enterprise computing for example - the issue of using the Grid for distributed, highly interactive applications has been raised. In our case this has emerged within a project seeking to build a European Learning Grid Infrastructure (ELeGI). Distributed learning environments need to be engaging and responsive, and as such it is important that, in addition to the dynamic resource sharing, service-oriented model offered by the Grid, that it can also meet the responsiveness needs of end users. In this paper we extend earlier work on analysing delay in distributed interactive applications to investigate the performance of the foremost Grid toolkit, Globus, in the context of distributed learning.