ietf-openpgp
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Re: PGP Message Exchange Formats Internet Draft

1997-08-08 04:39:57
Hello to all,

at 09:39 08.08.1997 +0200 Cees de Groot (>) wrote:

assar(_at_)sics(_dot_)se said:
Do you really see a new for more than 256 algoritms? 

Some people didn't see a need for more than 640k, either...

For this one byte, you step from likely exhaustion of your cypher-id space to 
very unlikely exhaustion. If people pick this up, start experimenting, 
etcetera - yes I can envision more than 256 algorithms. 65536, on the other 
hand, should be enough.

Well, here are my 2 cents to this context: One of the most wide-spread and
commonly used graphic-file-format ist the well-known Tif-format: It has been
designed to be able to imply all future needs by specifying them in tags
when needed with the effect that programs are downward-compatible. Thus it
now lasts for at least 5 years which is a relatively long period compared
the lifetime of hard- & software.

I think one should reserve at least 4 bytes ( each consisting of 8 bits :-)
) of data thus being able to roughly specify algorithms in ASCII-digits ( (
each consisting of 7 bits preceded by a '0' ;-) ) or directly being able to
use 2**28 = 268,435,456 or even 2**31 = 2,147,483,648 different algorithms (
each or the first byte beginning with a '1' ). This is even more than any
key-sub-space commonly used by beginners.

Best regards,

Hagen


-- 
_____________________________________________________________________
Hagen Wollert                               
h(_dot_)wollert(_at_)tu-clausthal(_dot_)de
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