Privacy With a 4096 Bit RSA Key — Offline, On Paper

HavanaF writes "Online backup is practical, but can it offer any privacy? The Dutch security company Safeberg developed an Offline Private Key Protocol, with an asymmetric key scheme. The protocol demands that the private (decryption) key be stored away from the 'source' computer, which presumably is 'too vulnerable.' The catch is that the private key needs to be fairly large to be secure: a 4,096-bit RSA key should suffice for some years. But how to store an 800-character key offline? Safeberg introduces a machine readable paper key, with the 4k-bit key crammed in a giant 2D Datamatrix barcode. This video on key strength tells the story."

Comments

What Happens When ...

[WrongSizeGlass]

... you fold the paper your 2D key is on? Tears, that's what. Tears.

Re:What Happens When ...

[Yvan256]

you can recover the data from the entropy in the universe.

I tried do to that and all I got was "42".

Another plausible scenario I have to watch out for

[Merc248]

Guy holding knife and laxatives: "Poop the paper! Poop it now!"

key exchange

[akirapill]

I'll fax you a xerox of my public key. Is analog the new steam punk?

Re:no thanks my Hard drive is too big

[toastar]

How the fuck am I gonna back up to a remote server over the internet at 60 kbytes/sec?

you can get about 17 MBytes/Sec with a 1.5TB through USPS

Re:Another plausible scenario I have to watch out

[Merc248]

"Defecate thy papyrus!"

Re:And this is practical, how?

[Arthur Grumbine]

Safeberg also announced that their official position is that "dog food tastes terrible".

Idiotic

[evilviper]

This makes absolutely no sense. Smart cards have been around for many years now. There, you NEVER give ANYONE or anything access to your private key. Challenge-response, one-time-passwords, tokens, etc, etc. Putting it on paper is LESS SECURE than sticking it on a thunb drive. Then at least it can't be stolen by taking a picture...