QuaLa - Quality of Service Language


About QuaLa

A major requirement for many contemporary service-oriented business systems is to comply to contracts and agreements, such as Service Level Agreements (SLA). SLAs are contracts between service providers and service consumers that assure that service consumers get the service they paid for and that the service fulfills the SLA’s requirements, such as availability, accessibility, or performance. Service providers need to know what they can promise within SLAs and what their IT infrastructure can deliver. To validate SLAs, mainly the services' performance-related Quality-of-Service (QoS) properties services are collected and utilized during the services runtime. The Quality of Service Language (QuaLa) provides the facilities for describing an SLA's performance-related QoS properties, such as availability or processing time. QuaLa is separated into two sub-languages. One language, the high-level QuaLa, is tailored for experts of the QoS domain and provides constructs for specifying the services’ QoS constraints that should not be violated during the system’s runtime. The high-level QoS constraints need additional technical details, so that we can generate the services and the QoS monitoring infrastructure automatically. Hence, the second language, the low-level QuaLa, extends the high-level QuaLa and is tailored for technical experts for specifying the additionally needed technical details about how and where to measure the required QoS properties. For more information about QuaLa and the applications of our framework we recommend to read the papers listed below.


The source code is available under open source license at https://sourceforge.net/projects/quala2010/.

A brief user guide can be found here.


Ernst Oberortner

Publications about QuaLas

  • E. Oberortner, U. Zdun, S. Dustdar: Tailoring a Model-Driven Quality-of-Service DSL for Various Stakeholders, MiSE'09
  • H. Tran, T. Holmes, E. Oberortner, E. Mulo, A. Betkowska Cavalcante, J. Serafinski, M. Tluczek, A. Birukou, F. Daniel, P. Silveira, U. Zdun, S. Dustdar: An End-to-End Framework for Business Compliance in Process-Driven SOAs, SYNASC'10

QuaLa related Publications

  • E. Oberortner, U. Zdun, S. Dustdar: Patterns for Measuring Performance-Related QoS Properties in Distributed Systems, PLoP'10
  • E. Oberortner, U. Zdun, S. Dustdar, A. Betkowska Cavalcante, M. Tluczek: Supporting the Evolution of Model-driven Service-Oriented Systems: A Case Study on QoS-aware Process-driven SOAs, SOCA'10
  • E. Oberortner, U. Zdun, S. Dustdar: Domain-specific Languages for Service-oriented Architectures: An Explorative Study, ServiceWave'08