What block cipher mode of operation encrypts plaintext and computes a message authentication code to ensure that the message was created by the sender and that it was not tampered with during transmission?

Galois and Counter (GCM)

Explanation:

 The galois and counter are one of the mode type that encrypt the given plan text and also compute the MAC (Message authentication code ) so that they ensure that the message are not tampered by sender during the process of transmission.

The GCM is basically define for the block cipher and the block size is 128 bits. Each block cipher has different types of mode of the operation according to their particular performance and the efficiency.

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