Page 154 - Hardware Implementation of Finite-Field Arithmetic
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Operations over  Z [ x ]/ f ( x )   137
                                                               p

                          p     m     LUTs   Slices  Total time
                          17    8     40     24      8
                          239   17    136    68      10

                        TABLE 5.2  Cost and Delay of Subtractors of
                        Polynomials mod p


               5.5.3  Adders/Subtractors of Polynomials mod p
               The cost and delay of several subractors are shown in Table 5.3.


                        p      m      LUTs   Slices  Total time
                        17     8      112    64      10
                        239    17     425    221     12

                      TABLE 5.3  Cost and Delay of Adders/Subtractors of
                      Polynomials mod p


               5.5.4 Serial Multipliers
                                                                  17
                                  17
               The circuits are for 239  with irreducible polynomial f(x) = x  + 237.
               The parameter Mult 18  ×  18 represents the number of embedded
               multipliers used in the Xilinx FPGAs. The cost and delay of these
               serial multipliers are shown in Table 5.4.


                                            Mult
                   p   m   FFs  LUTs  Slices  18 × 18  Period  Cycles  Total time
          MSE-first  239  17  303  1,690  937  17  26.1   34    888
          LSE-first  239  17  415  1,779  1,061  18  19.4  17   330

          TABLE 5.4  Cost and Delay of Serial Multipliers


               5.5.5 Exponentiation
                                                               17
                                17
               The circuit is for 239  with irreducible polynomial f(x) = x  + 237. The
               parameter Mult 18  ×  18 represents the number of embedded
               multipliers used in the Xilinx FPGAs.

                                           Mult                    Total
           p    m    FFs    LUTs   Slices  18 × 18  Period  Cycles  time
           239  17   1,241  3,989  2,318   36       19.5   289     5636
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