MoDe4SLA - Monitoring Dependencies for SLAs


Although web services are intended for short-term ad-hoc-collaborations, in practice, many Web service compositions are offered longterm to customers. While the Web services making up the composition may vary, the structure of the composition is rather fixed. For companies managing such Web service compositions, however, challenges arise which go far beyond simple bilateral contract monitoring. For example, it is not only important to determine whether or not a component (i.e., Web service) in a composition is performing properly, but also to understand what the impact of its performance is on the overall service composition.

In the MoDe4SLA project we have elaborated important requirements existing for the monitoring of service compositions. In particular, we provide a sophisticated approach for determining the impact each web service (of a composite service) has on the composition at runtime. More precisely, MoDe4SLA identifies complex dependencies between Service Level Agreements (SLAs) in a service composition. By explicating these dependencies, causes of SLA violations of a service might be explained by malfunctioning of the services it depends on. MoDe4SLA assists managers in identifying such causes.

We are also evaluating the MoDe4SLA approach concerning usefulness for the user as well as effectiveness for the business. Usefulness is evaluated by experts who are asked to manage simulated runs of service compositions using MoDe4SLA. Their opinion on the approach is an indicator for its usefulness. Effectiveness is evaluated by comparing runtime results of SLA management using MoDe4SLA with runtime results of unsupported management. Criteria for effectiveness are cost reduction and increase in customer satisfaction.


  • University of Twente, Information Systems Group, The Netherlands
  • University of Ulm, Institute of Databases and Information Systems


MoDe4SLA has been partially funded by the Netherlands Organization for Scientific Research (NWO) in the context of the COOP project


2008 - 2011

Additional Information


| 2011 | 2010 | 2009 | 2008 |


Bodenstaff, Lianne and Wombacher, Andreas and Reichert, Manfred (2011) Empirical Validation of MoDe4SLA; Approach for Managing Service Compositions. In: 14th International Conference on Business Information Systems (BIS'11), Poznan, Poland , June 2011, LNBIP 87, Springer, pp. 98-110. file


Bodenstaff, Lianne and Wombacher, Andreas and Reichert, Manfred and Wieringa, Roel (2010) MaDe4IC: an abstract method for managing model dependencies in inter-organizational cooperations. Service Oriented Computing and Applications (SOCA), 4(3): 203-228, Springer. file
Bodenstaff, Lianne (2010) Managing Dependency Relations in Inter-Organizational Models. Phd thesis, University of Twente. file


Bodenstaff, Lianne and Wombacher, Andreas and Wieringa, Roel and Jaeger, Michael C. and Reichert, Manfred (2009) Monitoring Service Compositions In MoDe4SLA: Design of Valdiation. In: Proc. 11th Int'l Conf. on Enterprise Information Systems (ICEIS'09), Volumne on Software Agents and Internet Computing, Milan, Italy, pp. 114-121. file
Bodenstaff, Lianne and Wombacher, Andreas and Reichert, Manfred and Jaeger, Michael C. (2009) Analyzing Impact Factors on Composite Services. In: 6th Int'l Conf. on Services Computing (SCC'09), Bangalore, India, September 2009, IEEE Computer Society Press, pp. 218-226. file
Bodenstaff, Lianne and Wieringa, Roel and Wombacher, Andreas and Reichert, Manfred (2009) Towards Management of Complex Service Compositions. In: IEEE World Congress on Services, Part II, SERVICES II, Int'l Workshop on Service Computing for B2B (SC4B2B'09), Bangalore, India , September 2009, IEEE Digital Library, IEEE Computer Society Press , pp. 160-167. file


Bodenstaff, Lianne and Wombacher, Andreas and Reichert, Manfred and Jaeger, Michael C. (2008) Monitoring Dependencies for SLAs: The MoDe4SLA Approach. In: IEEE 5th Int'l Conference on Services Computing (SCC 2008) , Honolulu, Hawaii, USA, July 2008, IEEE Computer Society Press, pp. 21-29. file