[Cryptography] Future GPG/PGP

Ray Dillinger bear at sonic.net
Wed Sep 30 14:54:58 EDT 2015

On 09/29/2015 02:18 PM, Michael Kjörling wrote:

> (Just because I could, when I replaced a SSH connection key recently,
> I went with a 6144 bit modulus. Neither system involved is
> particularly underpowered by modern standards, but the SSH
> authentication using that key is _noticably_ slow.)

Which sort of reminds me of Adam Back's hashcash scheme for limiting
email rates, except that it more specifically limits *connection* rates
instead and email is not usually from the party who bears the cost of

Hmmm.  This could be used as a tactic against some forms of sybil
attack where the attacker has to contact *MANY* nodes in a short time
in order to be successful. Considering that SSH is a pre-existing
part of many protocols whereas it's really difficult to add support
for something like Hashcash to a protocol.

Instead of the asymmetry of calculating vs checking a hash partial
collision, you have the asymmetry of defenders getting to split up
the work among themselves and attacker not.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://www.metzdowd.com/pipermail/cryptography/attachments/20150930/3ac22b01/attachment.sig>

More information about the cryptography mailing list