Message Authentication Codes
Message Authentication Codes (MACs) are cryptographic techniques used to verify the authenticity and integrity of a message. They involve generating a short piece of information (the MAC) from a secret key and the message, which can be checked by a recipient with the same key to detect any tampering or forgery. MACs ensure that data has not been altered in transit and originates from a trusted source.
Developers should learn and use MACs when building secure systems that require data integrity and authentication, such as in network protocols (e.g., TLS/SSL), API security, or file verification. They are essential for preventing attacks like data tampering or replay attacks, especially in scenarios where confidentiality is not the primary concern but trust in the data's origin and state is critical.