10 Important interview Questions on SOA

1) What is SOA? 

Service Oriented Architecture (SOA) is used to develop Enterprise applications by using a collection of services which communicates each other. Service-Oriented Architecture (SOA) is a set of principles and methodologies for designing and developing software in the form of interoperable services. 

2) What is a pick activity? Can I have a pick activity with no onMessage branch? 
Pick activity picks the messages from service (Source) which has multiple operations or the BPEL process needs to receive the messages from multiple source system. Pick activity should have at least on Message branch. 

3) What is the difference between 10g and 11g?

SCA architecture was followed in 11g and not in 10g 

In 11g you can put all your project SOA components in composite.xml file and deploy as a single deployment unit to single server, where in 10g you have to deploy each component to the respective server (i.e. ESB to ESB server, BPEL to BPEL Server)
Basically all the SOA components like BPEL, ESB (Called Mediator in 11g), & OWSM are brought into one place in 11g using SCA composite concept.
The major difference between 10g & 11g would be the app server container. 10g by default runs onOC4J while 11g runs on Web logic Server.
In 10g every BPEL is a separate project, but in 11g several components can make 1 project as SCA.
In 10g consoles are separate for BPEL and ESB, but in 11g Enterprise Manager contains all.
In 10g BAM and business rules are outside SOA Suite, but in 11g they are in SOA Suite. 

4) Is Oracle SOA same as Oracle Fusion Middleware? 
No because SOA is one of the parts in Fusion middleware and SOA behaves like user interface where as Fusion is big platform

5) What is SCA? 
Service Component Architecture (SCA) provides a programming model for building applications and systems based on a Service Oriented Architecture. SCA is a model that aims to encompass a wide range of technologies for service components and for the access methods which are used to connect them. 

6) What is the SOA Suite 11g Components? 
Oracle Adapters
Oracle Mediator
Business Events and Events Delivery Network
Oracle Business Rules
Human Workflow
Oracle Business Activity Monitoring
Oracle Enterprise Manager 

7) What is choreography? How does it differ from orchestration? 
In choreography there is no business process to control the integration between the systems; each system will directly integrate with one another in sequence where as in Orchestration there is a business process which controls all the services (source/Target) which is part of the integration. 

choreography as "the specification of interactions between autonomous processes".

refers to specifications for how messages should flow among diverse, interconnected components and applications to ensure optimum interoperability. 

8) What are the different design patterns in SOA? 
Synchronous 
One Way(Fire and Forget)
Asynchronous (Delayed Response) 

9) In how many ways can a process be deployed? 
Using Jdeveloper
Through Enterprise Manger Console
Through Weblogic Scripts. 

MDB – Message Driven Beans in Weblogic Server.

we need to ensure that the dspMaxThread value is not greater than Receiver Threads. 

10) What is singleton Property in SOA? 
In the clustered environment when the processing of the message should happen via only one SOA managed server, then the property singleton needs to be defined at the adapter level.