CCM (Counter with CBC-MAC
) is a mode of operation for cryptographic Block Ciphers
CCM mode is an authenticated encryption algorithm designed to provide both authentication and confidentiality.
CCM mode is only defined for Block Ciphers with a block length of 128 bits.
The nonce of CCM must be carefully chosen to never be used more than once for a given key. This is because CCM is a derivation of CTR mode and the latter is effectively a Stream Cipher.
There might be more information for this subject on one of the following: