New secure channel coding scheme based on randomly punctured quasi-cyclic-low density parity check codes

A new joint cryptography-channel coding technique is introduced which employs punctured quasi-cyclic-low density parity check (QC-LDPC) codes obtained from extended difference families. The absence of permutation and scrambling matrices reduces the key size compared with similar code-based cryptosystems, while having an acceptable level of security. The main advantage of this system is that, provided the system parameters are chosen appropriately, even if the code employed is revealed the system remains secure. Performance results are presented which show that the punctured code outperforms a random low density parity check (LDPC) code of the same length and rate.