Abstract—Cloud computing is becoming a new application model for small and medium-sized enterprises to share hardware and software resources on-demand over the Internet. Despite the flourish of the cloud computing, there are many challenges, including establishing a model to make the cross-domain business collaboration between enterprises possible. In this paper, we present the concept of the community cloud, in which, resources can be integrated as services, for the community cloud members to collaborate with each other flexibly and quickly. We design a community cloud platform (CCP) model to support cross-domain business collaboration. We subsequently specify the formal definition of the functional components in the community cloud platform and give a detail analysis of the business collaboration engine of the platform.