Page 163 - ISCI’2017
P. 163

p  the length of symbol in binary representation will be l and the number of possible modes will
                                                                      1 p
              1
            be defined as  2  p l  1  . Where degree of alphabet extension can be assessed as

                                                   µ 2  =  2  p l  1  2  m l  = 2  p l  1  m l −  .


               During transformation according to module  p  the length of symbol in binary representation will

                                                                        p l
            be  l , and the number of possible modes will be defined as  2 . Degree of alphabet extension during
                p
            switching to transformation according to  p  will be:


                                                   µ 1  =  2  p l  2  1 p l  =  2  p l  1 p l −  .


               Correspondingly the possibility of guessing an alphabet symbol according to module  p  is defined
                                                                                                  1
            as

                                                     P =   1    =  2  m l  1 p l −  .                                                       (24)
                                                       1 p   µ 2

               The possibility of guessing an alphabet symbol according to module  p  is defined as

                                                      P =  1 µ 1  = 2  p l  1  p l −  .                                                        (25)
                                                       p

               Thus theorem is proved. The general possibility of guessing an alphabet  P  symbol according to
                                                                                       G
            module  p  during switching from  m -ary source to  p-ary will be defined with multiplication of events

             P  (24) and  P  (25),  i.e.:
               1 p         p

                                               P =  P ⋅ P = 2  m l  p l −  1  ⋅ 2  p l  1  p l −  = 2  m l  p l −  .                                       (26)
                                                          p
                                                G
                                                     p 1
               Using (26) the one can define complexity  I  of one alphabet symbol  according to module  p
                                                           G
            during switching from  m -ary source to  p-ary  as

                                                    I =   1 P в  = 2  p l  m l −  .
                                                     G

               Thus while  applying of generator scheme without hashing the complexity  I         KR   of key

            reconstruction  X =  K 0  i +  is determined with a formula:


                                                                                 ( ) ).                          (27)
                                                                                     1
                                                                         ( ) ln
                                            I KR  = I G  ⋅ I DL  = 2  p l  − m l  ⋅exp (ε ln p  υ  ln p  ( υ−  )
               For a case of applying of generator schemes with guessing a  field element, discrete logarithm
            solution and hashing the complexity  I KRH   of key reconstruction  X =  K 0  i +  is determined with  a

            formula:


                                                                          υ
                                                                   ( ln p
                                      I KRH  = I G  ⋅ I DL  ⋅ I H  =  2  p l  − m l  ⋅ exp ε  ( ) ln ln p  (1−υ )  n 2  .                     (28)
                                                                                ( ) ) 2⋅

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