Enforcing Integrity of Execution in Distributed Workflow Management Systems

Frederic Montagut, Refik Molva
2007 IEEE International Conference on Services Computing (SCC 2007)  
As opposed to centralized workflow management systems, the distributed execution of workflows can not rely on a trusted centralized point of coordination. As a result, this flexible decentralized setting raises specific security requirements, such as the compliance of the overall sequence of operations with the pre-defined workflow execution plan, that are not yet met by existing decentralized workflow infrastructures. In this paper, we propose new security mechanisms capitalizing on onion
more » ... ption techniques and security policy models in order to assure the integrity of the distributed execution of workflows and to prevent workflow instance forging to name a few features. These mechanisms can easily be integrated into distributed workflow management systems as our design is strongly coupled with the runtime specification of decentralized workflows. The workflow execution further proceeds as depicted in figure 5 . For i ∈ [2, n−1] the business partner b i assigned to the vertex v i receives {l n−i+1 (O)} P K pol i , peels one layer off by decrypting it using SK poli , reads l n−i+1 (O) to retrieve SK i and sends {l n−i (O)} P K pol i+1 to b i+1 . AND-SPLIT workflow pattern. In the case of the AND-SPLIT pattern, the business partners (b i ) i∈[2,n] assigned to the vertices (v i ) i∈ [2,n] are contacted concurrently by b 1 assigned to the vertex v 1 . In this case, n − 1 vertex private keys should be delivered to (b i ) i∈[2,n] and the upper layer of the onion O 1 available to b 1 therefore wraps SK 1 and n − 1 onions (O i ) i∈[2,n] to be sent to (b i ) i∈ [2,n] as depicted in figure 6 .
doi:10.1109/scc.2007.57 dblp:conf/IEEEscc/MontagutM07 fatcat:yrcgm5kfxzaljapxgk4xgt5jya