Does service composition suffice to define business contracts for IT services in networked organizations

Abstract

Currently several enterprises depend on services provided to them by other parties for the realization of their own service offer. The interconnections in terms of services offered and required by companies shape complex systems, called service networks. The new cloud-computing paradigm is stressing the concept of the governance of relationship between IT customers and providers. The relationship is based on Service Level Agreements (SLA) and obligations, described inside contracts between providers and customers. Every customer needs to agree with a SLA in order to lease a new service. SLAs describe provisioning terms and encapsulate QoS characteristics as well as functional properties. Traditionally, providers define SLAs in which they guarantee explicit provisioning service level bounds for an agreed period. In the scientific literature, SLAs are hardly viewed as end-user documents, and merely as automated processes that assist the monitoring and scheduling of resources. In contrast, cloud IT marketplaces treat SLAs as static documents that do not allow for any processing. Moreover, strong diversity exists in how service providers coming from distinct business and socio-economical domains formulate and exercise their provisioning responsibilities. Such issues need to be resolved in order to make SLAs enacting tools for managers and services' providers in order to govern contracts. The contribution of this paper is to discuss some relevant open issues not covered by current contract management approaches and tools. In particular we will explore how service composition, with specific focus on service levels, limits and shapes technical, legal and organizational aspects related to the contract of the composed service.