Federal SOA

Notes: A Work in Progress and Initial Source: Capability Cases: A Solution Envisioning Approach, Polikoff, Coyne, and Hodgson, 2006, pp. 437-445, Addison Wesley.

Agile Methods:

Lightweight software development methodologies that emphasize close collaboration between the programmer team and business experts; face-to-face communication (as more efficient than written documentation); frequent delivery of new deployable business value; tight, self-organizing teams; and ways to craft the code and the team such that the inevitable requirements churn is not a crisis.

See the Agile Alliance Website

Component-Based Development:

An approach to the design and implementation of software applications where systems are assembled using components from one or more sources. The components may be written in different programming languages and run on different platforms. Components exist at different levels of granularity - from a re-usable calendar gadget to fully featured CRM (Customer Relationship Management)) module. What is common is their ability to be composable. A software component is any self-contained, independently viable, and deployable grouping of services whose services can be involked by many different types of clients.

See Componenttechnology.Org Website

Model Driven Architecture (MDA):

An approach to system specification, portability, and interoperability based on the use of formal and semi-formal models. The MDA derives all executable code from models of the system using UML and other associated OMG (Object Management Group) standards.

See the OMG MDA Website

Ontology:

A model of how to specify a subject area of interest in which concepts, their attributes, and relationships (associations between concepts) are explicitily named and distinguished. Constraints stipulate distinctions that differentiate concepts, governing how they participate in relationships, and how implicit knowledge is made explicit through qualifiers that allow inferencing over relationships properties. A standard language for representing an ontology on the web is the W3C standard OWL.

See W3C Semantic Web Website

Semantic Model:

Another way of referring to Ontology, usually used in the context of IT solutions that employ an ontology an execution time.

A semantic model in which relationships (associations between items) are explicity named and differentiated is call ontology. Because relatiobships are specified, there is no longer a need for strict strucuture that encompasses or defines the relationships. The model essentially becomes a network of connections with each connection having an association independent from any other connection.

Semantic Web:

An evolution of the Web to a web in which meaning can be exchanged and mediated to provide machine-to-machine and more effective human-to-machine interaction. Descrived as "a common framework that allows data to be shared and reused across application, enterprise, and community boundaries. It is a collaborative effort lead by W3C with participation from a large number of researchers and industrial partners. It is based on the Resources Description Framework (RDF), which integrates a variety of applications using XML for syntax and URIs for naming.

See W3C Semantic Web Website

Semantic Web Technology:

Semantic Web Technology is the technology that is enabling the Semantic Web and refers to technologies such as RDF, RDFS, and Owl.

See W3C for RDF, RDFS, and OWL

Service-Oriented Architecture (SOA): See Multiple Definitions by Organizations Below.

A Service-Oriented Architecture (SOA) defines how two computing entities interact in such a way as to enable one entity to perform a unit of work on behalf of the another entity. The unit of work is refered to as a service, and the service interactions are defined using a description language. Each interaction is self-contained and loosley coupled, so that each interaction is independent of any other interaction.

Taxonomy:

A tree-like hierarchical structure of information. Taxonomies are often used by Internet portals (such as Yahoo!), online catalogs, and Web stores to categorize information and to offer consistent navigation. Taxonomical hierarchies provide an ordered connection between each item in the strucuture and the item or items below it.

Unified Modeling Language (UML):

Developed by the Object Management Group, UML is a visual language for specifying and documenting models of software systems, including their strucuture and design. UML is supported by many development tools.

See the OMG UML Website

Web Service:

A software application whose interfaces and binding are capable of being defined, described, and discovered through industry-standard XML protocols, such as SOAP, WSDL, and UDDI.

SOA Defined by OMG, Oasis, Open Group, W3C, and Wikipedia:

OMG: Service Oriented Architecture is an architectural style for a community of providers and consumers of services to achieve mutual value, that:

• Allows participants in the communities to work together with minimal co-dependence or technology dependence
• Specifies the contracts to which organizations, people and technologies must adhere in order to participate in the community
• Provides for business value and business processes to be realized by the community
• Allows for a variety of technologies to be used to facilitate interactions within the community

Oasis: Service Oriented Architecture (SOA) is a paradigm for organizing and utilizing distributed capabilities that may be under the control of different ownership domains.

• In general, entities (people and organizations) create capabilities to solve or support a solution for the problems they face in the course of their business. It is natural to think of one person’s needs being met by capabilities offered by someone else; or, in the world of distributed computing, one computer agent’s requirements being met by a computer agent belonging to a different owner. There is not necessarily a one-to-one correlation between needs and capabilities; the granularity of needs and capabilities vary from fundamental to complex, and any given need may require the combining of numerous capabilities while any single capability may address more than one need. The perceived value of SOA is that it provides a powerful framework for matching needs and capabilities and for combining capabilities to address those needs.

Open Group: An architectural style that supports service orientation Service orientation.

• A way of a way of thinking in terms of services and service based development and the outcomes that services bring Service
• A logical representation of a repeatable business activity that has a specified outcome (e.g., check customer credit; provide weather data, consolidate drilling reports), is self-contained and maybe composed of other Services. It is a black box to consumers of the 
  Service Architectural Style
• The combination of distinctive features in which Enterprise Architecture is done, or expressed The SOA Architectural style’s distinctive features: Based on the design of the services comprising an enterprise’s (or inter-enterprise) business processes. Services mirror real-world business activity
• Service representation utilizes business descriptions. Service representation requires providing its context (including business process, goal, rule, policy, service interface and service component) and service orchestration to implement service Has unique requirements on infrastructure. Implementations are recommended to use open standards, realize interoperability and location transparency. Implementations are environment specific, they are constrained or enabled by context and must be described within their context. Requires strong governance of service representation and implementation Requires a “Litmus Test", which determined a “good services”

W3C: A Service Oriented Architecture (SOA) is a form of distributed systems architecture that is typically characterized by the following properties:

• Logical view: The service is an abstracted, logical view of actual programs, databases, business processes, etc., defined in terms of what it does, typically carrying out a business-level operation.
• Message orientation: The service is formally defined in terms of the messages exchanged between provider agents and requester agents, and not the properties of the agents themselves. The internal structure of an agent, including features such as its implementation language, process structure and even database structure, are deliberately abstracted away in the SOA: using the SOA discipline one does not and should not need to know how an agent implementing a service is constructed. A key benefit of this concerns so-called legacy systems. By avoiding any knowledge of the internal structure of an agent, one can incorporate any software component or application that can be "wrapped" in message handling code that allows it to adhere to the formal service definition.
• Description orientation: A service is described by machine-processable meta data. The description supports the public nature of the SOA: only those details that are exposed to the public and important for the use of the service should be included in the description. The semantics of a service should be documented, either directly or indirectly, by its description.
• Granularity: Services tend to use a small number of operations with relatively large and complex messages. Network orientation: Services tend to be oriented toward use over a network, though this is not an absolute requirement.
• Platform neutral: Messages are sent in a platform-neutral, standardized format delivered through the interfaces. XML is the most obvious format that meets this constraint.

Wikipedia: