Improving confidentiality of AES-CCMP in IEEE 802.11i

Abstract

This paper proposed a new method for Advanced Encryption Standard-Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (AES-CCMP) to eliminate security issues in current method including small effective key length and predictable structure of Nonce which increases the probability of Time-Memory Trade-Off (TMTO) attack. Proposed method suggests three solutions to overcome the mentioned weaknesses including random NonceKey, four way handshake alteration and Pseudo Random Function (PRF). Besides, proposed and classic methods are compared in terms of TMTO attack probability, avalanche effect, changes in neighbor blocks, memory usage and execution time. According to the results, the proposed method is completely resistant to TMTO attack. In addition, avalanche effect and change in neighbor blocks of proposed method are so near to optimized state and also, classic and proposed methods are approximately the same in case of memory usage and execution time.