taylor%hpdstma@HPLABS.HP.COM (Dave Taylor) (07/12/88)
I thought you might all be interested in the solution that my colleagues at HP France and I arrived at for our own HP internal version of X.400 and the delivery notification problem. The key, we realized, was to have the notification level tag directly associated with each address, but at the same time to have it sufficiently general to allow for future growth (if the '92 spec has new notification levels, for example) AND sufficiently succinct that it doesn't clutter up the email even further (which the AT&T X.400 -> 822 gateway does, for example). The solution? To have a three character suffix optionally associated with each address as it occurs within either the To: Cc: or `Bcc:' lines (we added blind carbon copy capabilities too). The code is: [B] for delivery/non-delivery notification [F] for delivery failure notification [D] for delivery notification with the default being '[F]' for non-delivery notification. So this meant that, with the use of Flatform OS Names, we had a typical header of: To: US/ATTMAIL///HP/HPL//Taylor:Dave:://[B] Subject: testing just a test which would then have the default headers added as appropriate by the processing agent (the UA in this case) (those headers include the obvious ones, like From:, Date: etc) (in X.400 notation, of course). In practice it seemed to work out quite well, and it was also easy to fit in to the existing mail system paradigm we were working with (eg. The Elm Mail System). [a full description of the Elm and X.400 project is in the final stages of review before being submitted to a journal for publication; probably "Unix Review". More details if people are interested...] Thoughts? -- Dave Taylor