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Issue No.04 - October-December (2008 vol.1)
pp: 187-200
Sidney Rosario , IRISA/INRIA, Rennes
Albert Benveniste , IRISA/INRIA, Rennes
Stefan Haar , INRIA Saclay, ENS Cachan
Claude Jard , ENS Cachan, IRISA, Bruz
Service level agreements (SLAs), or contracts, have an important role in web services. They define the obligations and rights between the provider of a web service and its client, about the function and the Quality of the service (QoS). For composite services like orchestrations, contracts are deduced by a process called QoS contract composition, based on contracts established between the orchestration and the called web services. Contracts are typically stated as hard guarantees (e.g., response time always less than 5 msec). Using hard bounds is not realistic, however, and more statistical approaches are needed. In this paper we propose using soft probabilistic contracts instead, which consist of a probability distribution for the considered QoS parameter—in this paper, we focus on timing. We show how to compose such contracts, to yield a global probabilistic contract for the orchestration. Our approach is implemented by the TOrQuE tool. Experiments on TOrQuE show that overly pessimistic contracts can be avoided and significant room for safe overbooking exists. An essential component of SLA management is then the continuous monitoring of the performance of called web services, to check for violations of the SLA. We propose a statistical technique for run-time monitoring of soft contracts.
Composite Web Services, Web Services, Quality of Services
Sidney Rosario, Albert Benveniste, Stefan Haar, Claude Jard, "Probabilistic QoS and Soft Contracts for Transaction-Based Web Services Orchestrations", IEEE Transactions on Services Computing, vol.1, no. 4, pp. 187-200, October-December 2008, doi:10.1109/TSC.2008.17
[1] R. Aggarwal, K. Verma, J.A. Miller, and W. Milnor, “Constraint Driven Web Service Composition in METEOR-S,” Proc. IEEE Int'l Conf. Services Computing (SCC '04), pp.23-30, 2004.
[2] G Anderson, “Nonparametric Tests of Stochastic Dominance in Income Distributions,” Econometrica, vol. 64, no. 5, pp. 1183-1193, 1996.
[3] T. Andrews, F. Curbera, H. Dholakia, Y. Goland, J. Klein, F. Leymann, K. Liu, D. Roller, D. Smith, I. Thatte, D. Trickovic, and S. Weerawarana, “Business Process Execution Language for Web Services,” version 1.1, OASIS, May 2003.
[4] J. Arias-Fisteus, L. Sánchez Fernández, and C. Delgado Kloos, “Applying Model Checking to BPEL4WS Business Collaborations,” Proc. Symp. Applied Computing (SAC '05), pp. 826-830, 2005.
[5] P. Baldan, A. Corradini, and U. Montanari, “Contextual Petri Nets, Asymmetric Event Structures, and Processes,” Information and Computation, vol. 171, no. 1, pp. 1-49, 2001.
[6] M. Basseville and I. Nikiforov, Detection of Abrupt Changes—Theory and Application. Prentice-Hall, Apr. 1993.
[7] A. Bertolino, G. De Angelis, A. Sabetta, and S. Elbaum, “Scaling Up SLA Monitoring in Pervasive Environments,” Proc. Int'l Workshop Eng. of Software Services for Pervasive Environments (ESSPE '07), pp. 65-68, 2007.
[8] P. Bhoj, S. Singhal, and S. Chutani, “SLA Management in Federated Environments,” Computer Networks, vol. 35, no. 1, pp.5-24, 2001.
[9] A. Bouillard, S. Rosario, A. Benveniste, and S. Haar, “Monotony in Service Orchestrations,” Technical Report 6658, Inria, Apr. 2008.
[10] G. Canfora, M. Di Penta, R. Esposito, and M. Luisa Villani, “An Approach for QoS-Aware Service Composition Based on Genetic Algorithms,” Proc. Genetic and Evolutionary Computation Conf. (GECCO '05), pp. 1069-1075, 2005.
[11] J. Cardoso, A.P. Sheth, J.A. Miller, J. Arnold, and K. Kochut, “Quality of Service for Workflows and Web Service Processes,” J.Web Semantics, vol. 1, no. 3, pp. 281-308, 2004.
[12] S. Chandrasekaran, G.A. Silver, J.A. Miller, J. Cardoso, and A.P. Sheth, “XML-Based Modeling and Simulation: Web Service Technologies and Their Synergy with Simulation,” Proc. Winter Simulation Conf., pp. 606-615, 2002.
[13] W. Cook and J. Misra, “Implementation Outline of Orc,” internal report, , 2005.
[14] A.C. Davidson and D.V. Hinkley, Bootstrap Methods and Their Application. Cambridge Univ. Press, 1997.
[15] V. Firoiu, J.-Y. Le Boudec, D. Towsley, Z.-L. Zhang, and J.-Y. Le Boudec, “Theories and Models for Internet Quality of Service,” Proc. IEEE, vol. 90, no. 9, pp. 1565-1591, 2002.
[16] S.-Y. Hwang, H. Wang, J. Srivastava, and R.A. Paul, “A Probabilistic QoS Model and Computation Framework for Web Services-Based Workflows,” Proc. Int'l Conf. Conceptual Modeling (ER '04), pp. 596-609, 2004.
[17] S.-Y. Hwang, H. Wang, J. Tang, and J. Srivastava, “A Probabilistic Approach to Modeling and Estimating the QoS of Web-Services-Based Workflows,” J. Information Sciences, vol. 177, no. 23, pp.5484-5503, 2007.
[18] A. Keller and H. Ludwig, “The WSLA Framework: Specifying and Monitoring Service Level Agreements for Web Services,” J.Network and System Management, vol. 11, no. 1, 2003.
[19] D. Kitchin, W.R. Cook, and J. Misra, “A Language for Task Orchestration and Its Semantic Properties,” Proc. Int'l Conf. Concurrency Theory (CONCUR '06), 2006.
[20] E.L. Lehmann and J.P. Romano, Testing Statistical Hypotheses. Springer Verlag, 2005.
[21] Z. Liu, M.S. Squillante, and J.L. Wolf, “On Maximizing Service-Level-Agreement Profits,” Proc. ACM Conf. Electronic Commerce, pp. 213-223, 2001.
[22] D.A. Menascé, “QoS Issues in Web Services,” IEEE Internet Computing, vol. 6, no. 6, pp. 72-75, 2002.
[23] J. Misra and W.R. Cook, “Computation Orchestration: A Basis for Wide-Area Computing,” J. Software and Systems Modeling, May 2006, doi:10.1007/s10270-006-0012-1.
[24] X. Thang Nguyen, R. Kowalczyk, and M. Tan Phan, “Modelling and Solving QoS Composition Problem Using Fuzzy DisCSP,” Proc. IEEE Int'l Conf. Web Services (ICWS '06), pp. 55-62, 2006.
[25] C. Ouyang, E. Verbeek, W.M.P. van der Aalst, S. Breutel, M. Dumas, and A.H.M. ter Hofstede, “Formal Semantics and Analysis of Control Flow in WS-BPEL,” Science of Computer Programming, vol. 67, nos. 2-3, pp. 162-198, 2007.
[26] The SWAN Project, http:/, 2008.
[27] F. Puhlmann and M. Weske, “Using the pi-Calculus for Formalizing Workflow Patterns,” Business Process Management, pp. 153-168, 2005.
[28] S. Rosario, D. Kitchin, A. Benveniste, W. Cook, S. Haar, and C. Jard, “Event Structure Semantics of Orc,” WS-FM, pp. 154-168, 2007.
[29] P.J. Smith, M. Shafi, and H. Gao, “Quick Simulation: A Review of Importance Sampling Techniques in Communications Systems,” IEEE J. Selected Areas in Comm., vol. 15, no. 4, pp. 597-613, 1997.
[30] H.G. Song and K. Lee, “sPAC (Web Services Performance Analysis Center): Performance Analysis and Estimation Tool of Web Services,” Business Process Management, pp. 109-119, 2005.
[31] W.M. P. van der Aalst, “Verification of Workflow Nets,” Proc. Int'l Conf. Application and Theory of Petri Nets (ICATPN '97), pp. 407-426, 1997.
[32] W.M.P. van der Aalst, B.F. van Dongen, J. Herbst, L. Maruster, G. Schimm, and A.J.M.M. Weijters, “Workflow Mining: A Survey of Issues and Approaches,” Data and Knowledge Eng., vol. 47, no. 2, pp. 237-267, 2003.
[33] W.M.P. van der Aalst and K.M. van Hee, Workflow Management: Models, Methods, and Systems. MIT Press, 2002.
[34] A. van Dijk, “Contracting Workflows and Protocol Patterns,” Business Process Management, pp. 152-167, 2003.
[35] XMethods, http:/, 2008.
[36] L. Zeng, B. Benatallah, A.H.H. Ngu, M. Dumas, J. Kalagnanam, and H. Chang, “QoS-Aware Middleware for Web Services Composition,” IEEE Trans. Software Eng., vol. 30, no. 5, pp. 311-327, May 2004.
[37] L. Zeng, H. Lei, and H. Chang, “Monitoring the QoS for Web Services,” Proc. Int'l Conf. Service Oriented Computing (ICSOC '07), pp. 132-144, 2007.
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