With the advent of public key / private key cipher algorithms , the encrypting key ( aka public key ) could be made public , since ( at least for high quality algorithms ) no one without the decrypting key ( aka , the private key ) could decrypt the message .
With the arrival of ( public key / private key ) cipher algorithms , the encrypting key ( aka , the public key ) could be made public , since ( at least for `` high quality '' ciphers ) no one without the decrypting key ( aka , the private key ) could decrypt the message .