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GEC 1: Recommended Elliptic Curve Domain Parameters Ver. 0.5
elliptic curve domain parameters secp256r1.
2.7.1
Recommended Parameters secp256k1
The elliptic curve domain parameters over
F p associated with a Koblitz curve secp256k1 are speciﬁed
by the sextuple T
=
(p ;a ;b ;G;n ;h ) where the ﬁnite ﬁeld
F p is deﬁned by:
p
=
FFFFFFFF
FFFFFFFF
FFFFFFFF
FFFFFFFF
FFFFFFFF
FFFFFFFF
FFFFFFFE
FFFFFC2F
=
2256
 232
 29
 28
 27
 26
 24
 1
= x3
The curve E: y2
+ax
+b over
F p is deﬁned by:
a
=
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000000
b
=
00000000
00000000
00000000
00000000
00000000
00000000
00000000
00000007
The base point G in compressed form is:
G
=
02
79BE667E
F9DCBBAC
55A06295
CE870B07
029BFCDB
2DCE28D9
59F2815B
16F81798
and in uncompressed form is:
G
=
04
79BE667E
F9DCBBAC
55A06295
CE870B07
029BFCDB
2DCE28D9
59F2815B
16F81798
483ADA77
26A3C465
5DA4FBFC
0E1108A8
FD17B448
A6855419
9C47D08F
FB10D4B8
Finally the order n of G and the cofactor are:
n
=
FFFFFFFF
FFFFFFFF
FFFFFFFF
FFFFFFFE
BAAEDCE6
AF48A03B
BFD25E8C
D0364141
h
=
01
2.7.2
Recommended Parameters secp256r1
The veriﬁably random elliptic curve domain parameters over
F p secp256r1 are speciﬁed by the sex-
tuple T
=
(p ;a ;b ;G;n ;h ) where the ﬁnite ﬁeld
F p is deﬁned by: