Counter Mode Cipher Block Chaining Message Authentication Code Protocol (Counter Mode CBC-MAC Protocol) or CCM mode Protocol (CCMP) is an authenticated encryption protocol designed for Wireless LAN products that implements the standards of the IEEE 802.11i amendment to the original IEEE 802.11 standard. CCMP is a data cryptographic encapsulation mechanism designed for data confidentiality, integrity and authentication. It is based upon the Counter Mode with CBC-MAC (CCM mode) of the Advanced Encryption Standard (AES) standard. It was created to address the vulnerabilities presented by Wired Equivalent Privacy (WEP), a dated, insecure protocol.
- Data confidentiality; ensures only authorized parties can access the information
- Authentication; provides proof of genuineness of the user
- Access control in conjunction with layer management
Because CCMP is a block cipher mode using a 128-bit key, it is secure against attacks to the 2<sup>64</sup> steps of operation. Generic meet-in-the-middle attacks do exist and can be used to limit the theoretical strength of the key to 2<sup>n/2</sup> (where n is the number of bits in the key) operations needed.