The concepts of choreography and orchestration, discussed in previous chapters, pertain to the management of inter- and intraprocess flow, respectively. The pervasive business-to-business (B2B) ecommerce concept of collaboration , whose name, like those of choreography and orchestration, conveys a sense of coordinating individual entities, has a subtly different meaning. The leading model for collaboration is found in the OASIS group's specification of the Business Process Specification Schema (BPSS),[*] an XML language that is part of the larger electronic business XML (ebXML) B2B system.
The key elements of BPSS are the following:
A business transaction is an exchange of data between two partners that is treated as an atomic unit of work; if it fails at any point, both partners agree that exchange is null and void. A business transaction has a requesting and a responding activity and optional signals (acknowledgment messages).
A binary collaboration is an exchange between two authorized partners, each of which performs a role (e.g., buyer and seller): one is the initiating role; the other is the responding role. The collaboration consists of a set of activities, each of which can be either a business transaction or another binary collaboration .
A multiparty collaboration is an exchange between more than two partners, though it is defined in terms of a set of binary collaborations. For example, ...