Newsletters

April 2015

PaaSport Semantic Model

PaaSport project has as goal to lift the barriers that cause the vendor lock-in problem and empower Cloud customers and Cloud application developers by allowing them to choose freely the Cloud PaaS offering that best fits their needs. This will also lead to encourage the entrance of European SME Cloud vendors in the PaaS market and to strengthen their market position relative to the big vendors. To achieve this goal PaaSport made an analysis of existing ontologies for cloud computing, in general, and PaaS, in particular, as well as the identification of the requirements the semantic models have to satisfy. In computer science terms, an ontology is a formal naming and definition of the types, properties, and interrelationships of the entities that exist in a particular domain of discourse. In addition, the report elaborates on the upper-level ontologies that have been reused and extended, so as to align the PaaSport semantic models with existing foundational schemata towards promoting reusability and knowledge sharing. In the scope of the PaaSport project, the use of semantic models is twofold:

  • Aligning the models of different PaaS offerings, thus resolving semantic interoperability conflicts among heterogeneous Cloud PaaS offerings that exploit diverse platform and application models, offered service descriptions, offered resources, Quality of Service, SLA formats, billing policies and other important issues (such as location of service or service certifications); and,
  • Bridging the gap between business application requirements and PaaS offerings capabilities, thus, facilitating the matchmaking and the identification of the specific PaaS that fulfills the business and technical requirements of a particular application.

If we want to add a new parameter to a concept we have only to declare the quality value of this parameter. Moreover, we could do the same for concepts. The application example in the following Figure describes the logic underlying our proposed model.
April 2015

PaaSport Technical Newsletter

PaaSport project has as goal to lift the barriers that cause the vendor lock-in problem and empower Cloud customers and Cloud application developers by allowing them to choose freely the Cloud PaaS offering that best fits their needs. This will also lead to encourage the entrance of European SME Cloud vendors in the PaaS market and to strengthen their market position relative to the big vendors. To achieve this goal PaaSport offers a semantically interoperable PaaS offerings marketplace that facilitates the publication and advertisement of available Cloud PaaS offerings, the identification and recommendation of the best-matching PaaS offering, and the seamless business application deployment and migration.

PaaSport Reference Architecture

PaaSport Reference architecture constitutes a thin, non-intrusive marketplace which relies on open standards. It is designed in order to receive a scalable, reusable, modular, extendable, and transferable approach consisting of four layers plus the PaaSport Semantic models interacting with each other.

In more details the layers that realize PaaSpor Architecture are:

  • Adaptive Front-ends that support seamless interaction between users and the PaaSport functionalities, through a set of configurable utilities that are adapted to the user�s role and preferences;
  • PaaSport Semantic Models that serve as the conceptual and modelling pillars of the marketplace infrastructure, for the annotation of the registered PaaS offerings and the deployed applications profiles;
  • PaaS Offering Recommendation Layer that implements PaaS offering discovery, recommendation and rating;
  • Monitoring and SLA Enforcement Layer that realizes the monitoring of the deployed business applications and enforces SLAs;
  • Persistence, Execution, and Coordination Layer that contains the repositories need from PaaSport marketplace. Also included in this layer is the PaaSport Unified PaaS API that is a common API exploited in order to uniformly interact with the heterogeneous PaaS offerings and the lifecycle management of the advertised PaaS offerings and the deployed business applications.
These layers communicate and integrate through a commonly used internal API that has been constructed and allows the creation of PaaSport semantically interoperable PaaS offerings marketplace.