Business process as a service - status and architecture

A Cloud Service is usually classified as Infrastructure as a Service, Platform as a Service or Software as a Service. This classification ist not sufficient, when Business Processes are considered. Therefore, Business Process as a Service (BPaaS) as next level of abstraction is in discussion. BPaaS is already an important topic for analysts and cloud providers. In the scientific community a discussion about BPaaS has been started. This contribution presents a literature analysis of the current state-of-the-art in BPaaS. In order to investigate how a Business Process can be built on top of a cloud service, a prototpye of an external application is presented, which is built on top of a cloud service using a RESTful API. For the realization of BPaaS existing architectures for cloud computing are discussed. A proposal for an advanced Architecture for Business Process as a Service is presented. Based on these findings, a brief outlook on future research questions concerning Business Process as a Service is derived. 1 Business Process as a Service A common classification of cloud services has been developed by the National Institute of Standards and Technology (NIST), which assigns cloud services to three layers [LTMBMBL11] • Infrastructure as a Service (IaaS), • Platform as a Service (PaaS) and • Software as a Service (SaaS). This classification starts with IaaS, which refers to basic services e.g. for storage and reaches up to SaaS, where applications are provided as a service. In this classification each level abstracts from the functionality of the level below. The next level of abstraction above SaaS is Business Process as a Service (BPaaS) [SPBB12]. BPaaS means not only that software is provided to the user as a service. BPaaS means as well to