title: Asymmetric cryptosystem using random binary phase modulation based on mixture retrieval type of Yang-Gu algorithm: comment.
abstract: We comment on the recent Letter, by Liu et al. [Opt. Lett.38, 1651 (2013)] in which a method to improve the security strength of the asymmetric cryptosystem (ACS) by Qin and Peng [Opt. Lett.35, 118 (2010)] was proposed. However, in accordance with Liu's methodology, we could easily find other more efficient ways to achieve their purpose. More importantly, we think it is vitally necessary to point out that there exists a widespread, fundamental misunderstanding on the concept of ACS, which has also been studied in a series of related works.
authors: Wenqi
authors: W
authors: He
authors: Xiangfeng
authors: X
authors: Meng
authors: Xiang
authors: X
authors: Peng