Difference between revisions of "G"

 
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The symbol ''G'' refers to a distinguished point on the secpt256k1 elliptic curve known as the ''generator'' or ''base'' point.  
 
The symbol ''G'' refers to a distinguished point on the secpt256k1 elliptic curve known as the ''generator'' or ''base'' point.  
  
Using elliptic curve point addition, one may add G to itself over and over again to form the sequence  
+
Using elliptic curve point addition, one may add ''G'' to itself over and over again to form the sequence  
  
 
''G'', ''G'' + ''G'' = 2''G'', ''G'' + ''G'' + ''G'' = 3''G'', ...   
 
''G'', ''G'' + ''G'' = 2''G'', ''G'' + ''G'' + ''G'' = 3''G'', ...   
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''G'' = 02 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798
 
''G'' = 02 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798
  
and in uncompressed form is:
+
and in uncompressed form it is:
  
 
''G'' = 04 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798 483ADA77 26A3C465 5DA4FBFC 0E1108A8 FD17B448 A6855419 9C47D08F FB10D4B8
 
''G'' = 04 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798 483ADA77 26A3C465 5DA4FBFC 0E1108A8 FD17B448 A6855419 9C47D08F FB10D4B8
 
This particular choice of ''G'' is chosen to be secure against attacks when used in the context of public key cryptography.
 
 
  
 
The order of ''G'' and the cofactor are:
 
The order of ''G'' and the cofactor are:
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*''h'' = 01
 
*''h'' = 01
  
The order ''n'' is the number of times ''G'' may be added to itself to get the identity. The cofactor ''h'' = 1 tells us that ''n'' is the order of the group of elliptic curve points, and therefore ''G'' generates the entire group.
+
The order ''n'' is the number of times ''G'' must be added to itself to get the identity. The cofactor ''h'' = 1 tells us that moreover ''n'' is the order of the entire group of elliptic curve points, and therefore ''G'' is a generator of this group.

Latest revision as of 14:16, 18 December 2019

The symbol G refers to a distinguished point on the secpt256k1 elliptic curve known as the generator or base point.

Using elliptic curve point addition, one may add G to itself over and over again to form the sequence

G, G + G = 2G, G + G + G = 3G, ...

and eventually every point on the elliptic curve will be generated in this sequence.


In compressed form G is given by:

G = 02 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798

and in uncompressed form it is:

G = 04 79BE667E F9DCBBAC 55A06295 CE870B07 029BFCDB 2DCE28D9 59F2815B 16F81798 483ADA77 26A3C465 5DA4FBFC 0E1108A8 FD17B448 A6855419 9C47D08F FB10D4B8

The order of G and the cofactor are:

  • n = FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFE BAAEDCE6 AF48A03B BFD25E8C D0364141
  • h = 01

The order n is the number of times G must be added to itself to get the identity. The cofactor h = 1 tells us that moreover n is the order of the entire group of elliptic curve points, and therefore G is a generator of this group.