HMAC

Hashed Message Authentication Code used to verify the integrity of the messages sent/received

Objectives

1. As the Hash Function, HMAC is also aimed to be one way, i.e, easy to generate output from input but complex the other way round.
2. It aims at being less affected by collisions than the hash functions.
3. HMAC reuses the algorithms like MD5 and SHA-1 and checks to replace the embedded hash functions with more secure hash functions, in case found.
4. HMAC tries to handle the Keys in a more simple manner.

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