Unix System Administration Handbook 1997 October/usah_oct97.iso/rfc/800s/rfc807.txt

Text File | 1991-10-16 | 11KB | 349 lines

Network Working Group                                          J. Postel
Request for Comments:  807                                           ISI
                                                         9 February 1982



                     Multimedia Mail Meeting Notes




Introduction

   A meeting was held at USC Information Sciences Institute on the 12th
   of January 1982 to discuss multimedia mail issues and experiments.
   The list of attendees is at the end of this memo.

Overview:

   This meeting was called to discuss common interests in multi-media
   computer mail experiments, and to agree on some specific initial
   experiments.

Review of Status:

   Review current status of multimedia efforts at CMU, ISI, MIT, COMSAT,
   BBN, UCL, SRI.

   CMU

      Using PERQ, Quip for fax, LPCM vocoder from LL, will get NEC board
      (3 chips) to replace vocoder.  Will have a stand alone voice I/O
      device that operates at 2400 baud (not packetized). Not working on
      IP/TCP.  Will use the IP and TCP from the BBN project. Already
      using the BBN Jericho developed Pascal IP and CFTP. Interested in
      word recognition of LPC digitized voice data. Planning to package
      a synthesiser, an analyzer, and a pitch tracker on one board.

   ISI

      Using TOPS20 (code in BLISS10), and starting to use PERQ (code in
      Pascal), RAPICOM 450 for fax.  Main interest is in the data
      structuring and message transport protocols.

   MIT

      Using Apollos, will program in MDL.  Use of Apollos still limited
      due to (1) MDL not completely implemented, (2) network interface
      not yet available (waiting on multibus  to then interface to
      Ethernet). Will get NEC CCITT fax machine. Looking into VAX+BBN
      BitGraph for future.  Main work to date in  design for sharing
      message data in a conceptualy centralized filing system.  Emphasis


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Multi-Media Mail Meeting Notes                           9 February 1982


      on efficient storage and manipulation of multirecipient messages,
      enclosures, citations, etc.

   COMSAT

      Using small 11s, Rapicom 450 and 500 fax machines, also have some
      LPC vocoders.  Substantial work has been done on encoding and
      decoding both Rapicom 450 and CCITT T.4 fax data, and also on
      manipulation of bitmap data (See RFC 803).

   BBN

      Using Jericho (code in Pascal). Will be building a prototype
      system with the aim of investigating problems of data distribution
      and privacy.  Trying to produce portable software currently in
      Pascal but may switch to ADA in the distant future.  Have IP and
      CFTP running, working on TCP. CFTP is a file transfer built
      directly on IP.

   UCL

      Using LSI-11, Rapicom 450 fax machine, Grinell bitmap display.
      May get PERQs (produced by ICL) in future.  Have done quite a lot
      of work on encoding/decoding for the Rapicom 450, and in bitmap
      manipulations (e.g., cleanup of noise, scaling, cut and paste).
      Interests in the relation of other types of display protocols to
      multimedia effort e.g., VIDEOTEXT and TELETEXT.

   SRI

      There are three multimedia mail projects at SRI,sponsored by DCEC,
      ARPA, and NAVELEX.  SRI is a subcontractor (with Sytek and DTI) to
      SDC in the DCEC program to produce protocol specifications for the
      DoD.  SRI has written service specifications for a mail system
      similar to RFC759+767 with security features added.  The ARPA
      project is studying the issues involved in a multimedia mail
      architecture based on RFC759+767, including negotiations,
      envelopes, and multilevel security.  The NAVELEX project is
      investigating user interfaces for command and control
      workstations, including natural language access to a data base.
      The plan is to use RFC759+767 data structures to communicate text
      and graphics, implemented on Foonly F-5s running Tenex with
      Foo-Vision displays.  The current choice for the graphics protocol
      is Bisbey's GL2.







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Multi-Media Mail Meeting Notes                           9 February 1982


Discussion:

   Coding/Decoding Algorithm:

      We agree to use the encoding specified in the CCITT T.4
      recommendation for the exchange of black and white bitmap data.

   New Equipment:

      It is reported that soon NEC will have CCITT T.4 Group 3 Fax
      machines for about $15K.

   NBS Mail Standard:

      The possibility that the NBS Mail Format Standard is a workable
      alternative to the RFC759+767 protocol is to be studied.  What is
      the relationship between these standards?  Do we have comment on
      the NBS Standard to submit to NBS?

   Equipment Variations:

      What happens if the receiver does not have equipment capable of
      protraying some of the data (e.g., dosen't have a  LPC vocoder)?
      There are three subtopics:  How many "standard" forms are
      allowed?, What do you tell the user if you can't do it?, and How
      does the cost of a medium (in memory or cpu cycles or portrayal
      time) effect its use? The general feeling was that if there is
      some type of data the receiving system can't portray, it should
      simply tell the user "There is some data here I can't portray and
      it's type is x.". The other aspects are items for further study.

   Negotiation:

      Does negotiation make sense in a mail system?  What are the kinds
      of things to be negotiated?  One possiblity is to initially send
      only pointers to the sections of a message, and have the recipient
      system ask for the parts it can handle.  Does this make sense in a
      message relaying environment?  Or for messsages with a fine scale
      interleaving of media types?  This topic is for further study.

   Enclosures, Pointers, Cross References:

      This seems too complex to handle at this meeting, so for now send
      the whole thing.  This is an item for further study.

   Editing Multimedia Objects:

      This is one of the most interesting parts of these research



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Multi-Media Mail Meeting Notes                           9 February 1982


      projects, so each group will develop their own techniques, and we
      will compare notes.

   Manipulation of Bitmaps:

      The issues involve aspect ratios, cut and paste, rotation  and,
      scaling. We need to compare notes and exchange algorithms.  An
      item for further study.

   Mailbox IDs and Control Information:

      With different types of source hosts and destination host
      (timsharing systems, personal computers) and different types of
      mail delivery schemes (append to file, query database server), do
      we have sufficient control mechanisms and addressing modes?  This
      is an item for further study.

   Storage and Transmission:

      How do the requirements for memory, disk, cpu, and transmission
      capacity differ for multimedia mail from text mail? This is an
      item for further study.

   Multimedia Virtual Message Format:

      It is not clear that this is anything different than what is
      specified by RFC759+767, but since it was not fully discussed it
      is an item for further study.

   Media Specific Protocols:

      Specific format definitions are needed for each media.  This is an
      item for further study.

   Interfaces to Other Systems:

      How do we interface this multimeda system to opther systems (e.g.,
      TELETEXT, VIDEOTEXT), and to text only mail systems (e.g.,
      ARPAMAIL, TELEMAIL, ONTYM).  This is an item for further study.

An Experiment:

   BITMAP-TEXT DOCUMENT EXCHANGE

      Move the data between computers as a file, using any file transfer
      method available.

      The File is a complete RFC 759 Document.



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Multi-Media Mail Meeting Notes                           9 February 1982


      Bitmap data is in revised COMSAT Image Data Format.

         Two compression types are to be used:

            Raw Bitmap

            CCITT Algorithm

      Text data is in RFC767 Paragraph Format.

Action Items:

   Start a New Note Series

      For the exchange of protocols, formats, algorithms, procedures,
      and other information between the multiamedia mail projects.

      By: Jon Postel

      Due: 1-Feb-82

   Update RFCs 759 & 767

      To remove typos and clairfy ambiguities.

      By: Jon Postel

      Due: 1-Feb-82

   Update "Image Data Structure" Memo

      To be more generally for bitmaps and not so focused on fax only.

      By: Anil Agarwal

      Due: 1-Feb-82

   Compare and Contrast NBS Mail Standard with RFC 759+767 Protocol

      Would the NBS Mail Standard be an adaquate alternative to the RFC
      759+767 approach?

      By: each site

      Due: Unspecified






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Multi-Media Mail Meeting Notes                           9 February 1982


   Issue the NBS Mail Standard as an RFC

      To aid in wide consideration of it. (Where does the online file
      come from?)

      By: Jon Postel

      Due: Unspecified

   Report on the differences between the NBS Mail Standard and other
   things.

      What are the differences between the NBS standard and the
      RFC759+767 protocol?, the IFIP plans?, the CCITT plans?, and the
      ISO plans?

      By: Debbie Deustch

      Due: Unspecified

   Demonstrate FAX-TEXT Document Exchange

      This demonstration is to be ready before and repeated at the User
      Interface Meeting at CMU.

      By: all sites

      Due: 19-20 April 82

Attendees:

   Duane A. Adams    DARPA/IPTO    Adams@ISI           [phone]
   Vint Cerf         DARPA/IPTO    Cerf@ISI            [phone]
   Harry Forsdick    BBN           Forsdick@BBN        [phone]
   Bob Thomas        BBN           BThomas@BBND        [phone]
   Gene Ball         CMU           Ball@CMUA           [phone]
   Anil Agarwal      COMSAT        Agarwal@ISID        [phone]
   David L. Mills    COMSAT        Mills@ISID          [phone]
   Dave Lebling      MIT           PDL@MIT-XX          [phone]
   Jon Postel        ISI           Postel@ISIF         [phone]
   Greg Finn         ISI           Finn@ISIF           [phone]
   Alan Katz         ISI           Katz@ISIF           [phone]
   Carl Sunshine     ISI           Sunshine@ISIF       [phone]
   David Elliott     SRI           wde@SRI-KL          [phone]
   Andy Poggio       SRI           Poggio@SRI-Unix     [phone]
   Zaw-Sing Su       SRI           ZSu@SRI-Unix        [phone]
   Steve Kille       UCL           UCL-Netwiz@ISIE  (uk) [phone]
   Peter Kirstein    UCL           PKirstein@ISIA   (uk) [phone]
   Bill Tuck         UCL           UKSAT@ISIE       (uk) [phone]


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