Encrypting and Hashing Data

You typically use asymmetric encryption for sending data across trust boundaries, such as one person sending another person an encrypted email. You also use it for sending a symmetric session key across an insecure communication channel so that you can then use symmetric encryption in further communication. On the other hand, you often use symmetric encryption for data at rest—on your hard drive, for example—and as a session key in a number of encrypted networking schemes.

Encryption Technologies Common to macOS and iOS

macOS and iOS provide a number of encryption technologies, including:

Encryption Technologies Specific to macOS

macOS provides a few additional APIs for performing encryption: