Top 25+ WCF Interview Questions and Answers - 1

Question: 1

What is Windows Communication Foundation (WCF)?

WCF is a distributed technology that provides a single, integrated platform or model called the service model to develop distributed applications for Windows.

With WCF, powerful and interoperable service oriented distirbuted applications can be developed.

WCF was introduced in .NET Framework to resolve the problem of inconsistency in the communication between different applications due to the usage of diverse distributed technologies, such as Microsoft Message Queuing (MSMQ), .NET remoting, XML Web Services, and Enterprises Services (COM+ services).

WCF not only resolves the inconsistency but also ensures the security and reliability of the distributed application and interoperability among the distributed application and interoperability among the distributed technologies.

Similar to the other distributed technologies, WCF also uses the Simple Object Access Protocol (SOAP) messages to exchange information between service and the clients.

Question: 2

What was the code name of WCF?

The code name of WCF was Indigo.

Question: 3

When was WCF introduced?

WCF was introduced with .NET Framework 3.0 in 2006.

Question: 4

Mention the different layers of WCF?

WCF has serviced oriented architecture and supports services as well as clients. A WCF application can act as both service and client. The WCF services and clients communicate with one another through messages. WCF provides different layers for this message system. There are four layers in WCF, which are as follows:

Contracts - Defines the different functionalities that are exposed by the service to the client.

Service runtime - Defines the various time behabiours of the service.

Messaging - Defines the channels that are used for processing and exchanging messages.

Activation and Hosting - Defines the way a WCF service is hosted.

Question: 5

What are the types of contracts available in WCF?

WCF has four main types of contracts, which are as follows:

Service contract

Operation contract

Data contract

Message contract

Fault contract