Re: a challenge (no solution yet)

[dman <dsh8290@rit.edu>]

On Thu, Oct 18, 2001 at 01:58:10PM +0200, martin f krafft wrote:
| goal: a 4-16 byte 7-bit character value that somehow encodes the time
|   of creation such that it can be extracted if the encoding scheme/seed
|   is known. the encoded value should be such that it is mostly
|   impossible to change it so as to yield a later time of creation to be
|   encoded. in general, changing the encoded value may well render the
|   data invalid.
| 
|   this is supposed to be a token that's valid for a limited amount of
|   time, after which, a new token has to be fetched. this token should
|   not be obvious (e.g. the timestamp) to prevent people from changing
|   it to be valid longer rather than fetching a new one.
| 
| can you do it? or is there a tool out there?

I honestly don't know, but maybe Kerberos is what you are looking for?
(I know nothing except little bits I've caught in passing about
kerberos)

-D