Final answer:
There are three modes of security in WCF: Transport Level Security (TLS), Message Level Security (MLS), and TransportWithMessageCredential Security (TMCS). The difference between Transport and Message Level Security is where the security is applied.
Step-by-step explanation:
In Windows Communication Foundation (WCF), there are three modes of security: Transport Level Security (TLS), Message Level Security (MLS) and TransportWithMessageCredential Security (TMCS). In TLS, the security is applied at the transport level, where SSL or TLS protocols are used to secure the communication channel. MLS applies security at the message level, where each message is encrypted and authenticated individually. TMCS combines both modes, applying transport level security and also providing message level security for certain operations.
The difference between Transport and Message Level Security lies in where the security is applied. In transport level security, security measures are applied at the transport layer, such as the encryption, authentication, and integrity checks at the level of the HTTP, TCP, or MSMQ protocol. On the other hand, message level security applies security measures at the message layer, allowing encryption, signing, and other security procedures to be applied at the level of the individual message itself.