Anton Stiglic wrote:
David Wagner [EMAIL PROTECTED] wrote:
martin f krafft wrote:
- Bob encrypts A(M) with key B and sends it to Alice
- Alice decrypts B(A(M)) with key A, leaving B(M), sends it to Bob
- Bob decrypts B(M) with key B leaving him with M.
Are there algorithms for this
On Tue, Nov 18, 2003 at 09:19:48AM -0800, Anton Stiglic wrote:
David Wagner [EMAIL PROTECTED]:
martin f krafft wrote:
it came up lately in a discussion, and I couldn't put a name to it:
a means to use symmetric crypto without exchanging keys:
- Alice encrypts M with key A and sends it to
Enzo Michelangeli wrote:
but the slight risk of collision,
although practically negligible, is a bit irksome
If you quantify the practically negligible risk, it might be less
irksome: SHA-1 is a 160 bit hash. The birthday paradox says that you
would need to hash 2^80 different credit card
David Wagner [EMAIL PROTECTED] wrote in message
news:[EMAIL PROTECTED]
martin f krafft wrote:
it came up lately in a discussion, and I couldn't put a name to it:
a means to use symmetric crypto without exchanging keys:
- Alice encrypts M with key A and sends it to Bob
- Bob encrypts
if something better can be done.
Enzo
- Original Message -
From: Amir Herzberg [EMAIL PROTECTED]
To: 'Enzo Michelangeli' [EMAIL PROTECTED]; [EMAIL PROTECTED]
Sent: Sunday, November 16, 2003 10:44 PM
Subject: RE: Are there...one-way encryption algorithms
Enzo asked,
Are there one-way
Enzo asked,
Are there one-way encryption algorithms guaranteed to be injective
(i.e., deterministically collision-free)? Or are there
theoretical reasons against their existence?
I'm looking for algorithms where every piece of code and data
is public, thus excluding conventional
