Composing Web Services in an Open World

This presentation reports on joint work with Loic Hélouët, Claude Jard, Sidney Rosario, the group of William Cook and Jayadev Misra at U.T. Austin, and the group of Serge Abiteboul at INRIA-Saclay Abstract: Wide area computing by combining services over the Web has recently gained significant momentum. P2P and Cloud computing are certainly evidences for this move. However, we believe that wide area distributed applications across organizations is also becoming a critical sector. Examples include e-administration, e-government, e-health, but also business processes, supplier chains, and automation systems. These distributed applications raise a number of difficult issues, e.g., functional correctness, security and privacy, as well as performance and QoS. The latter cannot be separated from the former, as many of these applications also require Operational Research and optimisation techniques, particularly so for supplier chains and automation systems. Information and workflow are equal citizen in these applications, and should not be handled separately using separated technologies. Finally, by being decentralized and resource agnostic, these applications must rely on contracts. In this talk I shall review and discuss some difficult problems originating from the above features and present some solutions.