rfc469.txt

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NWG/RFC#469                             Michael D. Kudlick MDK (SRI-ARC)
NIC 14798                               8-MAR-73

                      Network Mail Meeting Summary

Introduction

   The purpose of this RFC is to briefly summarize, from the NIC's
   viewpoint, the principal conclusions reached at the Network Mail
   Meeting held Friday, February 23 1973, at SRI-ARC.

      Please refer to RFC #475 (NIC 14919) for Abhay Bhushan's
      comprehensive summary of the issues discussed at the meeting.

      There is no major disagreement between the present RFC and RFC
      #475.

      RFC #453 (NIC 14317) contains background information on the
      meeting.

      RFC #479 (NIC 14948) describes what the NIC would like to see
      included in the File Transfer Protocol for Network Mail purposes,
      and also describes briefly how the NIC would use the information.

   The present RFC is organized as follows:

      Conclusions
      Discussion
      Attendees

Conclusions

   Additional FTP mail requirements were decided upon.  These would be
   implemented as a new mail command, with the following subcommands:

      TO

         This field is explicitly allowed to contain multiple
         addressees, with a standard syntax:  user@host.

      FROM

         This field provides a return-address for notification of
         undeliverable mail, as well as a clearcut identification of the
         sender for the recipient's information..






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      AUTHOR

         This field denotes the author of the mail.  There may be
         multiple authors

      TITLE
         The "title" (i.e. subject) of the mail is to be terminated by
         period carriage return.

      ACKNOWLEDEGMENT  success / failure (time out) / normal

         For use by the intermediate host, probably the NIC in most
         cases, to tell the sender what happened to his attempt to send
         mail.  (Note:  "normal" wasn't defined.)

      RECORDED  jnumber / null

         Note: "jnumber" is the pre-assigned accession number (NIC
         number), to be used when known.

         The "RECORDED" subcommand provides for the option of having the
         mail recorded.  Information given with this subcommand would be
         recognized at the NIC. Options are:

            to be recorded (in NIC journal) only,
            to be recorded and distributed,
            to be distributed only.

         This field would also be used to inform the recipient that the
         mail has been recorded.

            (In retrospect, it may be preferable to have a separate
            command to inform the recipient of this fact, but no
            decision on this was made at the 23-Feb-73 meeting.)

      TYPE  long / urgent / ordinary

         This allows the recipient site to take whatever action it
         thinks appropriate in storing the mail.

      TEXT / FILE / CITATION

         TEXT

            This field is for the text of the mail message.






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      FILE

         The purpose of the field is unclear to me.  Does it contain a
         machine readable pointer to the file that the sender wishes the
         recipient to read?

      CITATION

         This field is a person-readable pointer to the file that the
         sender wishes the recipient to read.  When the citation command
         is used, no mail is sent other than the citation.


Discussion

   Introduction

      The key aspects in the solution are:

         1) It is based on FTP.

         2) It uses the NIC without requiring direct use of NLS.

         3) There is a mechanism for uniformity in the use of
         user identifications.

         4) There is a mechanism for recording the mail for
         later reference.

      These issues are covered in the discussion that follows.

New FTP Mail Subcommands

   TO

      Addressee Format

         The standard form of the address is:  user@host

         "User" may be an individual's last name; or it may be whatever
         other identification the recipient has chosen AND has made
         known to the rest of the network.

            If the intended host doesn't recognize the intended
            recipient's identification, then it sends back an
            "undeliverable" mail message to the sender's host.  It is up
            to the individual to keep the NIC informed of his wherabouts
            [sic]; otherwise, he may not get his mail on time.



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      NIC Role

         The NIC need have no role at all for mail sent from point A to
         point B, whenever that mail is not to be recorded at the NIC.

         For mail that is to be recorded at the NIC, the RECORDED
         subcommand is to be used.

         Also, when the sender does not know the standard address of the
         recipients, he may use the NIC to obtain this information.

      Idents and Addresses

         The NIC will modify its identification files to include the
         "user@host" standard address for each individual.

            Sites may ask the NIC to translate from NIC Ident, or from a
            user's last name, to the standard address.  A query facility
            will be made available at the NIC to do the translation on
            request.  The translation service will also be available for
            "group idents".

            This service would be FTP-like, in term of the prootocol
            [sic] it accepts, but would not be within FTP itself.  A
            different server process would handle Ident translation
            requests.

            Translation will also be done at the NIC when the NIC is
            used as an intermediate point on the delivery route.

               The NIC could be an intermediate point for recording the
               mail as a NIC journal item, and for forwarding the mail
               to its ultimate destinations.  During this process, the
               NIC would translate from NIC idents to standard
               addresses.

      In the NIC ident files, provision already exists to specify
      hardcopy or on-line delivery of recorded (NIC Journal) mail.

            This provision will be extended to include a "network"
            attribute, which means "deliver the mail to the host of this
            person".

            The network attribute may be qualified by restricting all
            mail to be kept at the sender, with only a notification
            message actually mailed.





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            Notification would be in the form of a citation giving "to",
            "from", "title", "date of submission", and "location of
            mail".

      TIP Users

         To enable TIP users to have access to the mail system, both for
         sending and receiving mail, it was suggested that some hosts
         will have to be the "home" site for these users (but no more
         than one "home" site per user).

         That is, an account that allows a TIP user to send and receive
         mail will have to be established at such a host.

            For the present, any TIP user can use the SRI-ARC system for
            his mail requirements.

         An alternate solution, that TIP's be equipped with a hardcopy
         device that is continuously available for printing mail, was
         discarded in favor of the above approach.

   FROM

      The "FROM" command in FTP, identifies the sender in "standard
      address" form.

         This will allow "undeliverable" mail notices to be sent back to
         the originator.

            The default condition is that the sender's host must retain
            the mail until it is "delivered" to the recipient's host.

               "Delivered"  means that the recipient's host has accepted
               the mail. It does NOT mean that the recipient has READ
               the mail.

            Alternatively, the sender may designate that an intermediate
            host store the mail.  Then the intermediate host has the
            responsibility of storing the mail until it is "delivered"
            to all intended recipients.

         The "ACKNOWLEDGEMENT" command will allow an optional, positive
         acknowledgement to be given to the originator of the mail (the
         "FROM" addressee), stating that the mail was delivered.







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