You work as the Enterprise application developer at Domain.com. The Domain.com network consists of a single Active Directory domain named Domain.com. All servers in the domain run Windows Server 2003. The design of applications forms part of your responsibilities at Domain.com. Domain.com operates as a financial institution.
You have been asked to make a recommendation in terms of the technological design to meet the Domain.com requirements. The plan is to develop a component for Domain.com. And this component is to provide the business logic for the management of customer accounts. The component should meet certain technical requirements to serve the Domain.com needs. Following is a list of these requirements:
1. Instantiated classes must be reused by multiple threads.
2. Method calls must be rolled back in the event of a failure occurring.
3. Only certain users must have the ability to call certain methods. In your recommendation you should mention the appropriate technology that will meet these technological requirements.

What should you do?

A.
Recommend the use of Microsoft .NET Enterprise Services.

B.
Recommend the use of Message Queuing.

C.
Recommend the use of Extensible Markup Language (XML) Web services.

D.
Recommend the use of Microsoft .NET Remoting.

Explanation:
Microsoft .NET Enterprise Services will allow you to build applications and components that make use of COM+ services. It further allows you to develop components able of supporting transactions, just-in-time (JIT) activation. Object pooling, as well as role-based security. One of the requirements that should be met includes a roll-back method call in the event of failure. Object pooling will allow you to reuse class instances. And role-based security allows you to restrict method calls to specific users.
Incorrect answers:
B: Message Queuing will not work under these circumstances since though it will allow you to support component-to-component communication through messages; it does not support role-based security to restrict method calls to certain users.
C: You should not recommend the use of Extensible Markup Language (XML) Web services because although it allows one to support communication across different platforms by means of using open Internet Protocols. However, it does not support object pooling to reuse class instances. And this is one of the requirements that should be met.
D: .NET Remoting allows you to support communication across application domain boundaries by means of using remote method invocations; it does not provide transaction support to roll back in case of failure.