Abstract
The paper proposes an XML-based approach for a controlled distribution of documents, that must be subject to distributed and collaborative updates. In particular, the approach we propose allows one to attach a flow policy to a document, that partially or totally specifies the list of subjects that have to receive the document. Flow policies associated with documents can be dynamically changed during document transmission. Such modifications are regulated by a set of modification control rules, specified according to a model that we present in this paper. A key feature of the proposed solution is that a subject, upon receiving a document can also locally verify the correctness of the path and of the modification operations possibly performed over it, without interacting with other parties. In the paper, besides presenting the language to specify flow policies and modification control rules, we describe the suite of protocols we have developed to perform the above-mentioned checks on document paths.
