What is Secure Messaging?
Secure Messaging is maybe the most widely used feature in Open Platform. It enables a reader to open a secure communication link with an applet, using one of the key sets of the applet. This link is called secure channel and may be opened in two mores, usually called SM-MAC and SM-ENC.
SM-MAC guarantees data integrity by appending a MAC (Message Authentication Code) to the APDU data. The Card Manager performs integrity checking.