International Association
for Cryptologic Research

In this article, a new symmetric block cipher named MSEA is proposed. MSEA is based on ARX cryptographic design technique. MSEA is simple in nature due to the use of combinations of elementary operations like modular addition, bit-wise rotation and bit-wise XOR. In MSEA, plain text block, secret key, and number of encryption rounds are variable in size, while the size of cipher text is double of size of plain text. Data-dependant rotation is the most vital feature of MSEA through which the unpredictability of encrypted text is increasing. Key formation and encryption/decryption schemes of MSEA are significantly fast.