Message authentication code

A Message Authentication Code (MAC) is a cryptographic checksum on data that provides integrity and authenticity assurances on a message. It is designed to protect both the message content from being altered and the sender's identity from being impersonated. ### Key Features of a MAC: 1. **Integrity**: A MAC helps to ensure that the message has not been altered in transit. If even a single bit of the message changes, the MAC will also change, allowing the recipient to detect the alteration.