Page 248 - Hardware Implementation of Finite-Field Arithmetic
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228    Cha pte r  Se v e n


               7.7.9 Montgomery Squarer
               The circuits were generated for specific polynomials and results for
               fully combinationals and sequential circuits are shown in Tables 7.11
               and 7.12, respectively.


                            m      LUTs   Slices  Total time
                            8      6      3       3
                            16     16     8       3
                            32     67     35      6
                            64     193    99      8
                            128    418    214     25
                            163    267    147     20
                            233    117    74      7

                           TABLE 7.11  Cost and Delay of
                           Combinational Montgomery Squarer

                 m     FFs    LUTs   Slices  Period  Cycles   Total time
                 8     23     24     14      3.1     8        25
                 16    41     44     25      3.2     16       52
                 32    73     79     41      3.4     32       109
                 64    141    147    80      3.4     64       218
                 128   274    271    147     3.9     128      500
                 163   361    341    199     4.3     163      701
                 233   542    484    309     4.4     233      1,025

               TABLE 7.12  Cost and Delay of Sequential Montgomery Squarer
               7.7.10 Binary Exponentiation
               The circuits were generated for specific polynomials. The circuits are
               sequentials and the number of cycles depends on the amount of ones in
                                                      m
               exponents. The worst case is when exponent e = 2 − 1 (i.e., all ones). The
               cost and delay of binary exponentiation is shown in Table 7.13.

                                                   Average     Worst
            m     FFs      LUTs    Slices  Period  time (μs)   time (μs)
            8     68       82      48      4.0     0.22        0.35
            163   1,042    1,124   614     5.0     69          135
            233   1,539    1,477   865     5.0     140         275

           TABLE 7.13  Cost and Delay of Binary Exponentiation
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