Reversible gate-based cipher text using QCA for nanocommunication

In reversible computing, quantum dot cellular automata (QCA) have been established as an emerging research domain for designing cost-effective nanocircuits. In secure nanocommunication, at the cryptographic hardware level, QCA circuits can play a major role. The reversibility of the encoding and decoding technique in cryptography is a big issue. This paper describes the design of a reversible encoder using a Feynman gate based on QCA. The same circuit can also function as a decoder. By using the proposed encoder and decoder, secure nanocommunication is achieved. The quantum cost of the proposed encoder/decoder is 1, and the produced cipher text has only one garbage value. The proposed reversible encoder as well as the decoder consumes only 28 512 nm² of total area and three clock zones, while the nanocommunication circuit requires only 103 680 nm² of total area and 11 clock zones. The designed circuit can be used to design a more complex cryptographic hardware system at the nanoscale and protect against power analysis attacks. The implementation has been achieved using the QCADesigner tool. The theoretical value of the proposed design is compared with the generated simulation result that prescribes the functionality of the circuits.