service execution in workflow-like business processes and business activity monitoring (BAM). We have successfully demonstrated the usability and adequacy of our rule-based approach in various domains of research and industry use cases such as for ITSM and BAM (see RBSLA project [13]), Semantic Search (see GoPubMed project [8]), and Semantic Web-based virtual organizations and collaboration (see Rule Responder project [16]).

We argue that our rule-based design artifact (service-oriented CEP middleware + declarative rule language and rule engine) is a more expressive and adequate tool to describe complex event processing logic and business service executions than, e.g., the too much focused event correlation engines or the very restricted
"if-activity" rules in BPEL (BPEL 2.0) which are only based on simple material implications and not on the precise and expressive semantics of logic programming and non-monotonic reasoning formalisms. The clear logical semantics of our approach ensures traceability, verifiability and reliability of derived results and reactions. Ultimately, our rule-based design artifact might help to put the vision of highly flexible and adaptive business services networks with support for CEP, ITSM, BAM and BPM
into large-scale practice.

## 9. References [1] H. Boley. The Ruleml Family Of Web Rule Languages. In J. J.

Alferes, J. Bailey, W. May, and U. Schwertel, editors, PPSWR, volume 4187 of *Lecture Notes in Computer* Science, pages 1–17. Springer, 2006.

[2] H. Boley and S. Tabet. Ruleml: The ruleml standardization initiative, http://www.ruleml.org/, 2000.

[3] A. Bonner and M. Kifer. Transaction logic programming (or a logic of declarative and procedural knowledge). Technical report csri-323, University of Toronto, Nov. 1995 1995.

[4] S. Chakravarthy, V. Krishnaprasad, E. Anwar, and S. K.

Kim. Composite events for active databases: Semantics contexts and detection. In *VLDB 94*, pages 606–617, 1994.

[5] R. A. Kowalski and M. J. Sergot. A logic-based calculus of events. *New Generation Computing*, 4:67–95, 1986.

[6] A. Kozlenkov. Prova workflow patterns, http://www.prova.ws/etc/mule-prova-agents.zip, 2007.

[7] A. Kozlenkov, A. Paschke, and M. Schroeder. Prova, http://prova.ws. 2006.

[8] A. Kozlenkov and M. Schroeder. Prova: Rule-based java-scripting for a bioinformatics semantic web.

Proceedings International Workshop on Data Integration in the Life Sciences, 2004.

[9] J. W. Lloyd. Foundations of logic programming; (2nd extended ed.). Springer-Verlag New York, Inc., New York, NY, USA, 1987.

[10] Mule. Mule enterprise service bus, http://mule.codehaus.org/display/mule/home, 2006.

[11] A. Paschke. Eca-ruleml: An approach combining eca rules with interval-based event logics. Working paper, IBIS,
TUM, Technical Report, 11/2005 2005.

[12] A. Paschke. The reaction ruleml classification of the event /
action / state processing and reasoning space. White paper, Reaction RuleML Technical Group, October 2006.

[13] A. Paschke. Rule based service level agreements, http://ibis.in.tum.de/projects/rbsla/index.php, 2006.

[14] A. Paschke. A typed hybrid description logic programming language with polymorphic order-sorted dl-typed unification for semantic web type systems. In OWL-2006
(OWLED'06), Athens, Georgia, USA, 2006.

[15] A. Paschke. *Rule-Based Service Level Agreements -*
Knowledge Representation for Automated e-Contract, SLA
and Policy Management. IDEA, Munich, 2007.

[16] A. Paschke, H. Boley, A. Kozlenkov, and B. Craig. Rule responder: A ruleml-based pragmatic agent web, www.responder.ruleml.org, 2007.

[17] A. Paschke, C. Kiss, and S. Al-Hunaty. Npl: Negotiation pattern language - a design pattern language for decentralized (agent) coordination and negotiation protocols. In R. Banda, editor, E-Negotiation - An Introduction. ICFAI University Press, ISBN 81-314-0448-X, 2006.

[18] A. Paschke, A. Kozlenkov, H. Boley, M. Kifer, S. Tabet, M. Dean, and K. Barrett. Reaction ruleml, http://ibis.in.tum.de/research/reactionruleml/, 2006.

[19] M. Welsh, D. Culler, and E. Brewer. Seda: An architecture for wellconditioned, scalable internet services. In Proceedings of Eighteeth Symposium on Operating Systems
(SOSP-18), Chateau Lake Louise, Canada, 2001.