Take the 2-minute tour ×
Cryptography Stack Exchange is a question and answer site for software developers, mathematicians and others interested in cryptography. It's 100% free, no registration required.

In the Type A curve used in Pairing based Cryptography, what is meant by sign0 & sign1 in the expression below?

a_param struct fields:

exp2, exp1, sign1, sign0, r:
  r = 2^exp2 + sign1 * 2^exp1 + sign0 * 1 (Solinas prime)
q, h:
  r * h = q + 1
  q is a prime, h is a multiple of 12 (thus q = -1 mod 12)

Reference: http://crypto.stanford.edu/pbc/manual/ch08s03.html

share|improve this question
add comment

1 Answer

The values $\mathtt{sign0}$ and $\mathtt{sign1}$ are just signs, i.e., indicating negative or positive sign (elements from the set $\{-1,1\}$).

share|improve this answer
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.