rfc469.txt

RFC 的详细文档！


NIC 14798                                       MDK 8-MAR-73 17:24 14798


   AUTHOR

      The AUTHOR may be several persons. For recorded documents the
      authors appear separately in the index of authors, to facilitate
      searching for mail when an author is known, but the title and
      location of the mail are unknown.

   TITLE

      The TITLE field is especially useful for recorded mail, since
      indexes on key words in the title can be produced relatively
      easily, and facilitate searching for mail.

      For this reason, the title should be a succinct indicator of the
      contents.

   ACKNOWLEDGEMENT

      Acknowledgement of failure to deliver should be given to the
      sender.

         An optional, positive acknowledgement of successful delivery to
         the recipient's sitename will be given on request of sender
         (like U.S. CERTIFIED mail).

         No acknowledgement that the recipient actually saw the mail
         will be given (comparable to not having U.S. REGISTERED mail).

   RECORDED

      The concept of "recorded" mail is that a permanent record of the
      mail is kept centrally, to allow future references and re-readings
      of the mail to be made.

         For example, in the NIC Journal system, a record is kept of all
         the items entered into the Journal.  From this record, author,
         title-word, and NIC number indexes are produced to allow for
         references and re-readings.

         The key to retrieval of recorded Journal items is the use of an
         accession number (the NIC number).  This essentially removes
         the possibility of duplicate filenames being used.

      The basic aspect of recorded mail which was discussed at the mail
      meeting is the assignment of an "accession" number.






                                                                [Page 6]

NIC 14798                                       MDK 8-MAR-73 17:24 14798


         It was decided to get the accession numbers from the NIC on an
         as-needed basis, without pre-assignment and without local
         assignment of numbers.

         This subject may be reviewed in the future.  Local assignment
         may be desirable to prevent the NIC from becoming a bottleneck
         in the mail process.

         It was pointed out that local assignment of numbers would be
         un-ambiguous if the numbers included some information such as
         sitename, date, and time.

      One other problem exits [sic], namely "where is the recorded
      document?".

         Initially the document should be in the NIC, but ultimately it
         could be anywhere on the Network, provided only that there is a
         central mechanism for indexing and cataloging all the recorded
         documents.

         The pathname to the recorded document would then include
         filename and sitename.

   TYPE

      The TYPE subcommand was a result of a discussion on the
      problems of large mail files, and the associated
      question of who would pay for the processing and storing
      of these files.

      The main decisions made were:

         a) The processing, transmittal, and storage costs of
         sending mail should be borne at the sender's host.

         b) The processing and storage costs of receiving
         mail should be borne at the recipient's host
         initially, as a default.

      Information to enable the recipient host to make an
      intelligent decision about where to store the incoming
      mail are passed along via the TYPE command.

         The recipient host will have the local option of
         providing either of the following services:






                                                                [Page 7]

NIC 14798                                       MDK 8-MAR-73 17:24 14798


            a) free use of system to send mail;
            b) free use of system to receive mail, i.e. login
            not required for delivery over the Network.  (A
            possible alternative is use of a "mail" account,
            or use of the recipient's account, for processing
            and storage of the incoming mail.

   TEXT / FILE / CITATION

      TEXT

         This field is for the text of the mail message.

      FILE

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

      CITATION

         The citation is a person-readable pointer to the file that the
         sender wishes the recipient to read.

         An alternative to sending entire messages or files over the
         Network is to use the "CITATION" mechanism. With this, the
         sender sends a short message (the citation) saying, in effect,
         "please read file X at site Y".

            This alternative would be especially useful for

            a) mail that is distributed with group idents (to all
            liaisons, for example), and

            b) "long" files (size not defined) that the recipient may
            not be immediately interested in.

            However no method of enforcing use of this alternative was
            discussed.  It will be up to the recipients to devise a
            scheme satisfactory to them.

Other General Discussion

   Bob Kahn placed on the floor the following question (I paraphrase):

      Can't the design of a mail system be made to include alternative
      sources of data and alternative modes of operation, unless
      exclusion of these alternatives can be quantitatively defended?



                                                                [Page 8]

NIC 14798                                       MDK 8-MAR-73 17:24 14798


      Particular aspects of this question are:

      1) What is the desirability and difficulty of admitting different
      data sources into the mail system?

         What are the "boundaries" that divide permitted from prohibited
         data sources?

         What is the quantitative distinction between deferred and
         realtime mail?

         Will the design we come up with allow such things as

            a) handling a calendar that reflects the known and
            anticipated whereabouts of people so that meetings can be
            scheduled sensibly?

            b) formatting the mail contents for later query and other
            information handling?

      2) Whatever primitives we implement, can't they be designed so as
      not to preclude things like Tenex "linking"?

         This requires two-way data communication paths.

         How do we specify and get the attention of a "sink" for the
         data stream?

            e.g., for interprocess communication, and for Tenex-type
            "linking".

   The general reaction to this discussion was one of perspective:

      In the scheme of things that could be considered "point-to-point
      communication", mailbox-type of communication is not the most
      general kind.

      AKB listed several types of communication problems:

         program-program communication
         people-people real-time communication,  e.g.
         Tenex-type "links"
         computer teleconferencing
         mailbox communication: cataloging, storage
         protocols: host-host, telnet, file transfer






                                                                [Page 9]

NIC 14798                                       MDK 8-MAR-73 17:24 14798


      A design for a mailbox-type system won't be required to encompass
      the problems of, say, a computer teleconferencing system, which
      has attributes (real-time, video, very large volume of data to be
      transferred, to name some) that are not attributes of a mail box
      system.

Attendees at the Network Mail Meeting 2/23/73 at SRI-ARC

           Nancy Mimno             BBN
   ACB     Alan Bomberger  AMES-67
   AKB     Abhay Bhushan   MIT-DMOG
   AWH     Wayne Hathaway  AMES-67
   CHI     Charles Irby            SRI-ARC
   DHC     Dave Crocker            UCLA-NMC
   JBP     Jon Postel              UCLA-NMC
   JDH     Dave Hopper             SRI-ARC
   JEW     Jim White               SRI-ARC
   LPD     Peter Deutsch           PARC-MAXC
   MCK     Mark Krilanovich        UCSB-MOD75
   MDK     Mike Kudlick            SRI-ARC
   REK2    Bob Kahn                ARPA
   RKK     Rajendra Kanodia        MIT-MULTICS
   RST     Ray Tomlinson   BBN-TENEX



         [ This RFC was put into machine readable form for entry ]
         [ into the online RFC archives by Joseph Marshall 9/97  ]























                                                               [Page 10]