Identifying traffic of same keys in cryptographic communications using fuzzy decision criteria and bit-plane measures

The use of same keys for different messages is not safe in cryptography to secure cryptographic communications even if encryption algorithm is strong enough and possesses good cryptographic properties. Such communications can be analyzed to find meaningful information by cryptanalysts or adversaries. Use of same keys may happens if keys are not managed in cipher systems appropriately by customers. One should evaluate ciphers thoroughly and assure for non-repetition of keys prior to its usage for secure communications. The paper presents a methodology to identify and segregate traffic of cryptographic communications of images encrypted with same keys by exploiting bit-plane image characteristics and applying Fuzzy decision criteria. Results presented in the paper shows that the proposed Fuzzy classification method is able to identify images encrypted with same keys successfully and it seems very useful to consider for various pattern recognition and image analysis problems.