Cryptanalysis of a video encryption method based on mixing and permutation operations in the DCT domain

Wireless sensor network (WSN) needs efficient and secure and simple algorithms to be implemented in order to assure confidential communications between nodes and base station. The most suitable kind of algorithm seems to be the partial encryption ciphers. MPEG video encryption can be done by selecting the most significant parts of this sequence which are the group of pictures known as the I-frames. In this letter, we study the security of a partial video encryption method by Yang and Sun (Prog Nat Sci 18:1299-1304, 2008) that can be used in video nodes in a WSN. Based on the given analysis, it is demonstrated that the cryptosystem under study has serious weaknesses in the shuffling and the mixing processes which makes it vulnerable to chosen plaintext attack. Through the studied cipher, we question whether practitioners should design their own new ciphers for their specific applications or should they use well-known ciphers and fit them to their applications.