Christof Momm

Definition of Metric Dependencies for Monitoring the Impact of Quality of Services on Quality of Processes

Service providers have to monitor the quality of offered services and to ensure the compliance of service levels provider and requester agreed on. Thereby, a service provider should notify a service requester about violations of service level agreements (SLAs). Furthermore, the provider should point to impacts on affected processes in which services are invoked. For that purpose, a model is needed to define dependencies between quality of processes and quality of invoked services. In order to measure quality of services and to estimate impacts on the quality of processes, we focus on measurable metrics related to functional elements of processes, services as well as components implementing services. Based on functional dependencies between processes and services of a service-oriented architecture (SOA), we define metric dependencies for monitoring the impact of quality of invoked services on quality of affected processes. In this paper we discuss how to derive metric dependency definitions from functional dependencies by applying dependency patterns, and how to map metric and metric dependency definitions to an appropriate monitoring architecture.

A Combined Workload Planning Approach for Multi-tenant Business Applications

The upcoming business model of providing software as a service (SaaS) bears a lot of challenges to service providers. On the one hand, service providers have to guarantee a certain quality of service (QoS) and ensure that they adhere to these guarantees at runtime. On the other hand, they have to minimize the total cost of ownership (TCO) of their IT landscape in order to offer competitive prices. Introducing multi-tenancy is a popular way for reducing TCO. But this concept also creates the risk of overload situations due to interfering tenants. Existing approaches for creating tenant allocations which minimize TCO for a given set of SLAs mainly focus on interactive dialog systems. However, besides such dialog interactions most business applications still involve background batch jobs, which might also interfere with each other. In this paper, we therefore propose a novel combined workload and batch planning approach for multi-tenant business applications offered as service.

On Some Challenges in Business Systems Management and Engineering for the Networked Enterprise of the Future

Business value networks will become increasingly important in the world’s economy in the future. Their appropriate IT support must efficiently realize business collaborations between globally spread organizations. The ability to adapt to changing market and business requirements together with the ability to reflect the business adaptations on the level of the connected ICT systems constitute key challenges for the support of business network formations. In this paper, the evolution of business trends and business process support during the last decades is briefly addressed. After the introduction of a reference model of business value networks, this paper discusses some pressing research challenges that have to be addressed to realize business value networks and their ICT system support in the future.

Integrated Modeling of Technical and Business Aspects in Service Networks

The current trend towards a global services economy provides significant opportunities and challenges. For establishing complex services and delivering competitive advantages, several service providers have to work together. This collaboration creates a service network as an organizational form to be managed by a so-called service integrator. Within a service network, multiple dependencies between the resulting service and the contributions of the various service providers exist, on both technical and business aspects. In addition to the functional aspects, the non-functional service properties and respective service levels are of great importance. Successful joint management of the technical and business dependencies is a key prerequisite for the successful management of service networks.

Service Level Management for Service Value Networks

The ongoing trend towards a global services economy creates considerable market opportunities for various stakeholders. A service intermediary who offers complex services to customers and consumes services from suppliers and thus creates a service value network, faces the challenge of adhering to agreed service levels while minimizing associated costs, risks and potential penalties. Starting from a lifecycle model for service value networks, this paper identifies the service level management tasks to be performed by a service intermediary. For each of these tasks, supporting software tools have been developed. Together, they form an integrated tool chain which provides effective support for service level management of service intermediaries. The tools have been evaluated in case studies and industrial settings. The paper contributes the first study of an end-to-end service level management for service value networks.

Manageability design for an autonomic management of semi-dynamic web service compositions

Web service compositions (WSC), as part of a service- oriented architecture (SOA), have to be managed to ensure compliance with guaranteed service levels. In this context, a high degree of automation is desired, which can be achieved by applying autonomic computing concepts. This paper particularly focuses the autonomic management of semi-dynamic compositions. Here, for each included service several variants are available that differ with regard to the service level they offer. Given this scenario, we first show how to instrument WSC in order to allow a controlling of the service level through switching the employed service variant. Second, we show how the desired self-manageability can be designed and implemented by means of a WSC manageability infrastructure. The presented approach is based on widely accepted methodologies and standards from the area of application and web service management, in particular the WBEM standards.

Market agents with a sense for mechanisms

When software agents act on markets they typically face a predetermined market mechanism. Their strategies are a priori tailored by the agent designer to suit the market mechanism at stake. So, the market mechanisms are only considered and examined at design time. In this paper, we present an approach to how agents themselves can grasp market mechanisms at runtime, directly derive a valid interaction protocol and consider the mechanism structure for their strategies - even for mechanisms they have not known before. For exemplifying our ideas, we present a BPEL implementation of a reverse English auction that is based on the notion of an auction reference model and make the BPEL description available to the agent. We show how the agent will derive an interaction protocol - the valid behavior - and how it even forms a reasonable strategy when presuming some generic market knowledge and basic strategy building blocks