SOA
What is SOA?1) A paradigm for organizing and utilizing distributed capabilities that may be under the control of different ownership domains. It provides a uniform means to offer, discover, interact with and use capabilities to produce desired effects consistent with measurable preconditions.
2) SOA is a way to define a distributed system where several autonomous services work in conjunction by passing messages across boundaries using well defined interfaces.
PARTS OF SOA
1) Web services are APIs that can be accessed over a network, such as the Internet, and executed on a remote system hosting the requested services.
2) It has an interface described in a machine-processable format (specifically WSDL).
3) Other systems interact with the Web service in a manner prescribed by its description using messages, typically conveyed using HTTP with an XML serialization.
Process Orchestration:
Process of arranging the services in order to attain business processes using WorkFlows.
IT Modernization:
1) Process whereby legacy systems are transformed to a more modern SOA environment.
2) Derives information from multiple sources such as current user workflow, current user enhancement requests and very importantly the current application itself.
Has two components
1)Infrastructure Modernization
2)Application Modernization
IT MODERNIZATION TYPES
1) Re-host
2) SOA Wrapping
3)Automatic Migration
4) COTS Replacement
5) Re-architect
Implementing SOA
Factors to consider:
1) Determine clear business goal and scope
a)Goal: precise to solve specific business challenges
b) Scope: should not be massive such as renovate the entire IT infrastructure
c) Desired target SOA with modernization options specific to organization business driver.
2) Select Tool suite and vendor products:
a)Tool suite: support “hot-pluggable” framework – allowing legacy
b) Vendor products: provide powerful niche solutions with added values
Factors Prohibiting SOA modernization
1) Vendor Lock ins : Restrictions as many architectures are based on proprietary protocols and implementations.
2) Tight Coupling with components: distributed architectures typically link components directly to one another; could be costly to change the dependent.
3) Large Initial Investment: May Cost more and ROI can take long time.
4) Complexity : as the interactions between objects are often rich and complex, tough to implement SOA.
Benefits of SOA:
1) Reduce operation cost & ease of maintenance
2) Increase compliance
3)Increase flexibility
Categories: SOA