Cryptography Reference
In-Depth Information
Degree of the polynomial
Primitive polynomial
α 2 + α +1
2
α 3 + α +1
3
α 4 + α +1
4
α 5 + α 2 +1
5
α 6 + α +1
6
α 7 + α 3 +1
7
α 8 + α 4 + α 3 + α 2 +1
8
α 9 + α 4 +1
9
α 10 + α 3 +1
10
Table 4.9 - Examples of primitive polynomials
Galois field F 16 being made up of 16 elements, the binary representation of
an element of this field is done with the help of 4 binary symbols belonging to
F 2 . These 4 symbols are equal to the values taken by coecients a , b , c and d
respectively.
Elements
of the
field
Polynomial
representa-
tion
Binary representation
0
0
0000
1
1
0001
α
α
0010
α 2
α 2
0100
α 3
α 3
1000
α 4
α +1
0011
α 5
α 2 + α
0110
α 6
α 3 + α 2
1100
α 7
α 3 + α +1
1011
α 8
α 2 +1
0101
α 9
α 3 + α
1010
α 10
α 2 + α +1
0111
α 11
α 3 + α 2 + α
1110
α 12
α 3 + α 2 + α +1
1111
α 13
α 3 + α 2 +1
1101
α 14
α 3 +1
1001
Table 4.10 - Different representations of the elements of Galois field F 16
Search WWH ::




Custom Search