Dynamic Role Binding in Blockchain-Based Collaborative Business Processes
This addresses the need for flexible actor management in blockchain processes for untrusted parties, though it is incremental by building on existing platforms.
The paper tackles the problem of static role assignment in blockchain-based collaborative business processes by introducing a model for dynamic binding of actors to roles and a policy specification language with verification capabilities, with experimental results showing that enforcement cost scales linearly with roles and constraints.
Blockchain technology enables the execution of collaborative business processes involving mutually untrusted parties. Existing platforms allow such processes to be modeled using high-level notations and compiled into smart contracts that can be deployed on blockchain platforms. However, these platforms brush aside the question of who is allowed to execute which tasks in the process, either by deferring the question altogether or by adopting a static approach where all actors are bound to roles upon process instantiation. Yet, a key advantage of blockchains is their ability to support dynamic sets of actors. This paper presents a model for dynamic binding of actors to roles in collaborative processes and an associated binding policy specification language. The proposed language is endowed with a Petri net semantics, thus enabling policy consistency verification. The paper also outlines an approach to compile policy specifications into smart contracts for enforcement. An experimental evaluation shows that the cost of policy enforcement increases linearly with the number of roles and constraints.