SOA Ecosystem–Interconnected Principles, Patterns, and Frameworks - Applied SOA Patterns on the Oracle Platform - page 50

Security
Security standards and specifications will be discussed in Chapter 2 , An Introduction to
Oracle Fusion - a Solid Foundation for Service Inventory , and Chapter 7 , Gotcha! Imple-
menting Security Layers , dedicated to security and Oracle's approach for its implementa-
tion.
Interconnected WS-* standards
To understand how WS-* standards could help solve some problems that are not ad-
dressed by the simple model of contemporary SOA, we will walk through the process-
identification flow diagram shown in the next figure. This diagram is based on the interac-
tions of web-based services as native areas of the WS-* standards implementation. We
will start with the definition of the process as a number of services invocations, sequential
or parallel, with different durational and transactional requirements.
First, let's identify whether it is a long or short running process. Longevity is the subject
of technical and/or business timeouts. The first one is related to a time slot; here, your ser-
vices in composition could hold on to the active state without draining too many re-
sources. The second is set by business requirements and can be quite substantial (days,
weeks, and so on). Moving by the left lane, we will first look at the synchronous services
and the standards associated with them. In common cases, we could assemble service
compositions from different domains, so a Service Broker will be compulsory; it will
help us resolve the disparity of the data models, formats, and protocol bridging as well.
Also, brokering means that routing and mediation could be necessary for complex service
activities when more than two services are involved. In these cases, Service Broker will
act as a Composition Controller . Both of them are SOA patterns, arguably most-com-
monly used, and we will see their implementation in detail soon. If it's just a synchronous
single interaction between a service consumer and a service provider, it's called a primit-
ive activity. In general, the following two major standards must be taken into considera-
tion:
• WSDL should have a binding to a proper MEP; otherwise, communication simply
will not be possible.
• The WS-ReliableMessaging service must be implemented if a feeble con-
nection or slow response from a service message-receiver could affect service
activities. The application of this standard will ensure that the message is de-
livered or at least provide an acknowledgement about the state of the delivery.