The management and coordination of cross-enterprise collaboration is changing due to globalization, specialization and innovation; furthermore, it is changing also due to the adoption of service-oriented cloud computing (SOCC). SOCC provides means for value-chain automation that is supported by many service-oriented industry standards. In this new environment, enterprises face new challenges. Firstly, they need to semi-automatically find collaboration parties and learn about their identity, services, and reputation. Second, they need to source Business-Processes-as-a-Service (BPaaS) from these newly found third parties to provide them service value that they do not create in-house due to lack of resources or know-how. The contribution of this paper is twofold. First, it proposes a BPaaS-HUB architecture that enables speedy business-partner discovery and support for on-the-fly background checking. The architecture addresses the domain-independent requirements of the functionality, data-exchange protocol, and system behavior. Second, it indicates how to populate the architecture with existing services, thus, illustrating a rapid domain-specific instantiation of the BPaaS-HUB. The existence of BPaaS-HUB-type of services as "rendezvous locations" is required for the broad adoption of cross-enterprise collaboration (CeC) in a SOCC environments.