Policy-directed data movement in grids

One of the guiding principles of the grid is local (site) autonomy. Resource owners maintain control over their resources even when those resources are part of a larger grid. In other words, resource sharing in grids must be subject to the policies of the (local) resource owners. To date, not enough attention has been paid to describing, manipulating or enforcing explicit resource usage policies. Most existing grid systems have either implicit resource usage policies (with ad-hoc enforcement mechanisms) or support only limited types of policies (e.g., security policies). Systems that do provide some support for resource usage policies typically consider only CPU resources, leaving the provisioning of other resources on the grid unconstrained. This paper focuses on policies for grid storage resources. We have identified classes of policies for grid storage resource providers and have implemented an explicit policy-based architecture to manage and enforce them. This architecture consists of two components, MyPolMan, a service to express and manage policies, and .NET GridFTP, an enforcement mechanism for policy-based grid data movement. We show how this system allows grid users to access storage resources through a familiar API while allowing local system administrators to control resource utilization.