Contents 1 Introduction
The composition of services into a coherent business process is a difficult task while ensuring compliance with several different factors. One aspect that has been identified [26] [25] but is still not well understood is how information flows from one service to another with respect to different security criteria. The understanding of information flow requires trade-offs between complementary dimensions which are studied separately such as access control[13], trust management[11] or choreography verification [8]. For example, access control mechanisms are concerned about the release of information from the point of view of a service, but they do not specify how the information must be propagated in the composition through trusted services. Service choreographies are useful to verify the basic syntactic consistency of services interfaces, but they do not provide end-to-end interaction configuration support. Examples include establishing peer-to-peer interactions between different services for some interactions while executing other parts of the composition by a centralized unit for monitoring purposes. It is clear that a service composition environment can be chaotic due to the variety and the number of such restrictions.
