Privacy

Authentication

To ensure privacy, users must prevent anyone except intended recipients from reading messages. Authentication is one means of verifying identity between two communicating entities. The most common method of authentication is through the use of certificates. A certificate is a set of data that completely identifies an entity. A certification authority (CA) will issue a certificate only after that authority has verified the legitimacy of an entity.

Digital Signatures

Digital signatures can be used to distribute messages in plaintext format. The recipients can verify that messages are received from the actual authors and have not been tampered with. Signing a message does not alter the message; it simply generates a digital signature string that can be bundled with the message or transmitted separately.

Lesson Summary

The Microsoft Cryptography API provides an interface to cryptography service providers so you can encrypt, encode, and add authentication to Win 32-based applications that can be safely transmit sensitive information over nonsecure networks. Privacy and authentication are the two major concerns of transmitting secure information over a nonsecure network. Privacy is provided when the message is encrypted so it appears to be random characters . A decryption key is required to decipher the message. Authentication is used to ensure that only approved recipients can decrypt the message. Digital signatures can be used to authenticate a message, providing a way for you to verify that received messages are from the actual authors and have not been tampered with.