The invention relates to
information security technology, in particular to a virtual
genome-based
cryptosystem (VGC). The
cryptosystem is provided with two matched keys, of which one is a virtual
genome database (VGDB) consisting of random deoxyribonucleic acid (
DNA) sequences and the other one is a position table that virtual genes of the VGDB are randomly distributed in a two-dimensional
microarray, namely a virtual
DNA microarray chip (VDMC). Any
plaintext information can be freely written on the VDMC, namely points for forming the
plaintext information are selected from the VDMC
microarray. The selected points correspond to the virtual genes in the VGDB; small segments of
DNA sequences are randomly selected from the virtual genes; and the uniqueness of the small segments of DNA sequences in the VGDB is determined by using a common tool of the
bioinformatics, namely a basic local alignment search tool (BLAST), or other character string search algorithms such as a Knuth-Morris-Pratt (KMP)
algorithm and the like. A
cipher text is combined by the small segments of DNA sequences. The small segments of DNA sequences need only to perform BLAST on the VGDB during decryption, namely the points for forming the
plaintext information can be discovered, and the plaintext information can be restored according to the VDMC. Any non-VGDB sequence can be randomly inserted into the
cipher text and does not have any influence on the
encryption. Thus, the VGC is an excellent
information hiding system. In addition, the VGC key can be updated automatically so as to realize an indecipherable one-time-pad
system. The
cryptosystem is used for real-time quick secret information communication,
digital signature and identity
authentication.