Patent ID: 8411852

Claim:
A stream cryptographic method comprising: a communication channel between a first computer and a second computer; a diffusion-area A, wherein A contains an initial value A 0 and further, is a d 1 ×d 2 × . . . ×d m binary matrix with a combination of positions labeled sequentially from 1 to n; a diffusion mechanism F t 1 applied to A, notated AF t 1 in abbreviation, wherein AF t 1 =AF(p 1 , p 2 t 1 , . . . , p k ); a diffusion-medium S, wherein S is a m-dimensional binary matrix which includes an anchor positon {dot over (S)}; and further, comprising steps of: (I) generating, by the first and the second computers, and assigned bit for steam encryption/decryption by: (a) setting t 2 =1, A t 1 ×(t 2 −1) =A 0 ; (b) obtaining a new value A t 1 ×t 2 , wherein A t 1 ×t 2 −1) F t 1 , further comprising steps of: (i) setting t=1; (ii) setting s=1; (iii) letting A t 2 −1 =A, and performing A with a diffusion function F(p s ), whrein S overlaps A by {dot over (S)} anchoring to the position p s transforming into m-dimension coordinates (i 1 , i 2 , . . . , i m ), then AF(p s )=A⊕Ad 1i ⊕ . . . ⊕Ad mi ⊕S, 1≦p s ≦n; (iv) if s=k, then going to next step; otherwise, s=s+1, going back to Step(iii); (v) if t≢t 1 , then t=t+1, going to Step(ii); (c) outputting the assigned bit of A t 1× t 2 ; (II) encrypting, by the first computer, a bit of a plaintext stream in sequence, wherein the bit of the plaintext stream XORs with the assigned bit of A t 1 ×t 2 ; (III) decrypting, by the second computer, a bit of the ciphertext stream in sequence, received from the first computer, wherein the bit of the ciphertext stream XORs with the assigned bit of A t 1 ×t 2 ; (IV) going back to Step (b), and further, letting t 2 =t 2 +1.