PGP: sequencing messages

[Brian Morrison]

On Wed, 05 Apr 2000 13:55:10 -0300 (ADT), Trevor Smith wrote:

>I didn't look up the RFC in question but the word "server" seems to
>indicate that it isn't the client's job.

It doesn't have to be the client, but if you want to be able to say to
someone that "In message ID=<> I said that:" you need to have a local
record of what you sent with the ID included. The server only generates
the ID if it isn't already there.

>
>>    I know that servers will /add/ things that are missing if needed.  Some of
>>the things it may add are a domain to make an email address complete (eg
>>morpheus@rpglink.com versus morpheus), date (even though this is required by
>>RFC822, the server will add it at the time it gets the message) and, IMHO,
>>MSGID.  In short, it is standard and expected behavior that the agent that
>>generates the message assigns the MSGID.  This has been the practice on pretty
>>much everything that I can remember in email, news and even FTN.
>
>Perhaps a better question then is how are these IDs derived by
>*clients* so that they are guaranteed to be unique throughout the
>Internet? Or is uniqueness not required, contrary to what Brian
>indicates RFC822 says?

Uniqueness is required, but the client can guarantee it in exactly the
same way that a server can.
Mixture of random and static information. Just adding in the hostname
reduces the task to being almost trivial.

-- 
Brian Morrison                                  bdm@fenrir.demon.co.uk
              do you know how far this has gone?
               just how damaged have I become?
                                      'Even Deeper' by Nine Inch Nails