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The work of David Chaum on privacy showed the world that it could build a world of trust, but preserve privacy. On the back of the work around the ground-breaking RSA method, in 1983, David outlined [here][1]:

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import random
import libnum
from Crypto.Util.number import getPrime
from Crypto.Random import get_random_bytes
import sysprimebits=32
if (len(sys.argv)>1):
primebits=int(sys.argv[1])
if (primebits>128): primebits=128q = getPrime(primebits, randfunc=get_random_bytes)
p = getPrime(primebits, randfunc=get_random_bytes)
n=p*q
PHI=(p-1)*(q-1)
e=65537
d=libnum.invmod(e,PHI)
print ("e=",e)
print ("d=",d)
print ("n=",n)
k=random.randint(1,n-1)m=10
mstar = (m*pow(k,e,n)) % n
sstar = (pow(mstar,d,n)) % n
s = (pow(k,-1,n)*sstar) % n
print ("\nk: ",k)
print ("m*: ",mstar)
print ("s*: ",sstar)
print ("\nBob signing (Blinded): ",s)
s= pow(m,d,n)
print ("Bob's signing of message: ",s)
e= 65537
d= 2124181929009379037
n= 12366750569495532989
k: 5848566409051754306
m*: 10054324083273091146
s*: 12242772676557453579
Bob signing (Blinded): 2010459568356223927
Bob's signing: 2010459568356223927

Conclusions

And so David showed us a new way of transacting, and in a trusted way. At the core of his work was the rights to privacy. We need to follow David’s path in the future and build a more trusted digital work, and which has increased levels of trust.

Reference

[1] Chaum, D. (1983). Blind signatures for untraceable payments. In Advances in cryptology (pp. 199–203). Springer, Boston, MA.

Professor of Cryptography. Serial innovator. Believer in fairness, justice & freedom. EU Citizen. Auld Reekie native. Old World Breaker. New World Creator.

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