MUAC: Access control language for mutual benefits

In a collaborative distributed environment, users own a set of private resources that they possibly share with each other to achieve mutual advantages. The access to resources is regulated by a policy defined by each user in isolation, and independently of the others. However, typical access control languages allow defining policies that only check the roles or the attributes of the requesters and resources. But they do not impose a fair exchange of access grants by taking into account what requesters offer to others. Here, we present MuAC, a logic-based access control language designed for expressing mutuality. In particular, MuAC allows specifying conditions on what requesters must offer in exchange for using a particular resource.