WCF 
- Microsoft has introduced WCF for inter process communication. WCF let us to establish communication channels using
- TCP
- HTTP
- MSMQ
- IPC
- Peer Network
- Namespace “System.ServiceModel” is used for WCF.
Different ways to host WCF Service are
- IIS
- Self-Hosting
- WAS
In WCF modes of communication between server and client are
- One-Way
- Request-Reply
- Callback
Security features used in WCF
- Integrity
- Confidentiality
- Authentication
- Authorization
The essential components of WCF
- Service class
- End point
- Hosting Environment
How WCF works?
WCF will follow – “Software and Service Model”, in which all essential components are defined as services and this will be used by client program.
Difference between classic web services (ASMX) and WCF
Classic web service known as ASMX were using SOAP protocol for sending and receiving the messages over network and over HTTP protocol whereas WCF allows the communication to happen over any transport protocol.