Frequently Asked Questions
Service Component Architecture (SCA) was conceived through industry collaboration to provide a language-neutral programming model for building applications based on Service Oriented Architecture. First published in 2005, the Open SOA Collaboration (osoa.org) finalized the SCA 1.0 specification and submitted to OASIS for standardization in March 2007.
The SCA programming model benefits architectures where business function is partitioned as a set of services. These services are then assembled into solutions called composite applications to address a particular business need. In addition to providing a model to compose services, SCA can be utilized in the creation of service components to be used in composite applications. SCA helps application developers maximize productivity through focus on solving business problems with application code rather than protocols and locations.
While made up of many industry leading vendors, the Open SOA Collaboration is not intended to be a standards body. The current version utilized in the WebSphere Application Server V7 Feature Pack for SCA is SCA 1.0 based on the Open SOA Collaboration specification. The SCA 1.0 specification is currently being standardized through the OASIS Open Composite Services Architecture (CSA) Member Section. The OASIS standardized version of SCA, which only makes incremental updates to the Open SOA specification, is known as SCA 1.1.
The list of participating vendors and supporters is always increasing. Please see the list located at: http://www.osoa.org/.
OASIS Open CSA participants are listed here: http://www.oasis-opencsa.org/members.
No, it is not. Open CSA encompasses a set of specifications including SDO and SCA.
Yes. Apache is hosting a project called Tuscany which hosts the multi-lingual open source for SCA and supports data with SDO and JAXB. http://tuscany.apache.org/
The WebSphere Application Server V7 Feature Pack for SCA is based on the Apache Tuscany SCA Java implementation.
No. SCA is a complimentary technology and does not replace Java EE. SCA provides a composition model that offers a solution-centric view of what services exist in a composition and how they interact with one another. Java EE includes a broad technology stack to address the many requirements of enterprise application development.
The Feature Pack for SCA supports inclusion of EJB 2.1 and 3.0 components in a composition. EJB 2.1 and 3.0 components can be part of an SCA composition or call into or be called from a composition. This gives customers the choice to incrementally integrate their existing Java EE solutions into an SOA based architecture and receive the added benefits that SCA offers, that is flexibility and agility.
The scope of SCA and SOA transcends Java, in that the conceptual frameworks are designed to be language neutral. There are in fact several different language implementations of SCA underway in various communities: C++, PHP, BPEL, and Java. Each of the languages define their own specific implementation of SCA, retaining the key concepts of SCA, implementing the language neutral portions in a natural way to that specific language environment.
WebSphere Application Server V7 Feature Packs are optional product extensions that offer targeted, incremental new features and capabilities. Introduced with WebSphere Application Server V6.1, WebSphere Application Server Feature Packs allow IBM to balance the need for timely support of new function and standards with customers' need to extend the life of existing WebSphere Application Server investments.
The WebSphere Application Server V7 Feature Pack for SCA supports SCA 1.0 created through the Open SOA (OSOA) Collaboration and currently being standardized through OASIS Open Composite Services Architecture (CSA).
Enhanced support for application development utilizing the WebSphere Application Server V7 Feature Pack for SCA will be provided through IBM Rational Application Developer V7.5. Currently in Beta, the IBM Rational Application Developer V7.5 SCA tools will feature a graphical assembly editor for wiring and configuring SCA components and composites, support SCA Java annotations and integrate with WebSphere Application Server V7 to add, run, debug, remove and hot update SCA contributions. The Rational Application Developer SCA tools open beta is available at: http://www.ibm.com/software/awdtools/developer/application/.
Customers may utilize any desired integrated development environment (IDE) or editor to build composite applications and services using the Feature Pack for SCA. The IBM Information Center and IBM Education Assistant include education and instruction on how to build and configure SCA composites using standard text editing tools.
Apache Tuscany is an open source project that implements the SCA and SDO specifications based on the Open SOA Collaboration and OASIS Open CSA; and it provides the basis for the SCA container support in WebSphere.
Apache Tuscany users are encouraged to utilize the WebSphere Application Server V7 Feature Pack for SCA in order to take advantage of the deep integration with and robust capabilities offered in WebSphere Application Server V7; however, care must be taken to ensure that the Tuscany application has not exploited Tuscany-specific capability not supported in the feature pack.
No. WebSphere does not support Tuscany API nor SPIs unless formally documented in the WebSphere InfoCenter documentation.
Is the implementation of SCA in the WebSphere Application Server V7 Feature Pack for SCA the same as the implementation of SCA delivered in WebSphere Process Server and WebSphere Enterprise Service Bus V6.x?
No, they are at different versions of the SCA specification. The SCA implementation in WebSphere Process Server and WebSphere Enterprise Service Bus V6.x is based on SCA 0.5 (Classic SCA) while the WebSphere Application Server V7 Feature Pack for SCA is based on SCA 1.0. Customers who wish to create SCA 1.0 composites on WebSphere Application Server that wire to Classic SCA services on WebSphere Enterprise Service Bus or WebSphere Process Server may do so through the Web services binding.
Classic SCA was first introduced by IBM and other vendors in 2005. SCA 1.0 is based on the Open SOA Collaboration (osoa.org) specification which was released to OASIS for standardization in 2007. IBM will continue to work towards standardizing capabilities pioneered in Classic SCA on WebSphere Process Server and WebSphere Enterprise Service Bus.
The WebSphere Application Server V7 Feature Pack for SCA is not currently supported for installation or configuration into the same WebSphere binaries or profiles with stack products. Future statements of support may be provided by given stack products that choose to make the feature pack support available for customers in an integrated solution.
IBM supports interoperability between WebSphere Application Server Feature Pack for SCA composites and services located on WebSphere Process Server or WebSphere Enterprise Service Bus through the Web services binding.