[Cryptography] End-to-End, One-to-Many, Encryption Question

Bill Frantz frantz at pwpconsult.com
Thu Jun 12 02:35:58 EDT 2014


On 6/11/14 at 5:49 PM, kentborg at borg.org (Kent Borg) wrote:

>Is there a way to encrypt once with key A, super-encrypt with 
>key B1 (not knowing any other keys), and finally decrypt with 
>key C1 (not knowing any other keys)?  Or, super-encrypt with 
>key B2, then decrypt with key C2?

This problem is similar to the problem which would occur if an 
encryption algorithm was a group. If the algorithm is a group, 
then there is a key C which can decrypt a message which is 
encrypt(B, encrypt(A, text)). DES was proven to not be a group, 
making triple-DES a viable way to get the security of a longer 
encryption key.

Cheers - BIll

-----------------------------------------------------------------------
Bill Frantz        | I like the farmers' market   | Periwinkle
(408)356-8506      | because I can get fruits and | 16345 
Englewood Ave
www.pwpconsult.com | vegetables without stickers. | Los Gatos, 
CA 95032



More information about the cryptography mailing list