jroland@linux-migration.net [PGP-Basics]
2014-08-07 02:05:52 UTC
All of our uses of public key cryptography presume the availability of computers, but suppose civilization collapses and we still have a lot of messages to be encrypted and decrypted, perhaps to hide or reveal information needed for our survival. Assume we have on paper the encryption/decryption keys, but only pencils, paper, and an abacus.
How much time would it take a proficient abacus user to encrypt a 10k byte message, and then decrypt it again. Hours? Days? Months? Years?
The method needs to be sufficiently secure that manually encrypted messages could still not be brute-force decrypted centuries later when civilization has computers again (but not quantum computers).
I need a good estimate for a science fiction story, in which people with information from the distant future send encrypted messages to future generations the decryption of which needs data from celestial events that they know will happen but that have not happened yet. In other words critical parts of the decryption keys need data from celestial events like novae to complete them, but they don't want the messages decrypted until those events occur.
How much time would it take a proficient abacus user to encrypt a 10k byte message, and then decrypt it again. Hours? Days? Months? Years?
The method needs to be sufficiently secure that manually encrypted messages could still not be brute-force decrypted centuries later when civilization has computers again (but not quantum computers).
I need a good estimate for a science fiction story, in which people with information from the distant future send encrypted messages to future generations the decryption of which needs data from celestial events that they know will happen but that have not happened yet. In other words critical parts of the decryption keys need data from celestial events like novae to complete them, but they don't want the messages decrypted until those events occur.