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Network Working Group                                          J. PostelRequest for Comments:  807                                           ISI                                                         9 February 1982Multimedia Mail Meeting NotesIntroduction   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.  EmphasisPostel                                                          [Page 1]

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 (SeeRFC 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 toRFC759+767 with security features added.  The ARPA      project is studying the issues involved in a multimedia mail      architecture based onRFC759+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 useRFC759+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.Postel                                                          [Page 2]

Multi-Media Mail Meeting Notes                           9 February 1982Discussion:   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 theRFC759+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 researchPostel                                                          [Page 3]

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 byRFC759+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 completeRFC 759 Document.Postel                                                          [Page 4]

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 inRFC767 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 withRFC 759+767 Protocol      Would the NBS Mail Standard be an adaquate alternative to theRFC759+767 approach?      By: each site      Due: UnspecifiedPostel                                                          [Page 5]

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 theRFC759+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 82Attendees:   Duane A. Adams    DARPA/IPTO    Adams@ISI           (202) 694-8096   Vint Cerf         DARPA/IPTO    Cerf@ISI            (202) 694-3049   Harry Forsdick    BBN           Forsdick@BBN        (617) 497-3638   Bob Thomas        BBN           BThomas@BBND        (617) 497-3483   Gene Ball         CMU           Ball@CMUA           (412) 578-2569   Anil Agarwal      COMSAT        Agarwal@ISID        (301) 863-6103   David L. Mills    COMSAT        Mills@ISID          (202) 863-6092   Dave Lebling      MIT           PDL@MIT-XX          (617) 253-1440   Jon Postel        ISI           Postel@ISIF         (213) 822-1511   Greg Finn         ISI           Finn@ISIF           (213) 822-1511   Alan Katz         ISI           Katz@ISIF           (213) 822-1511   Carl Sunshine     ISI           Sunshine@ISIF       (213) 822-1511   David Elliott     SRI           wde@SRI-KL          (415) 859-4107   Andy Poggio       SRI           Poggio@SRI-Unix     (415) 859 5094   Zaw-Sing Su       SRI           ZSu@SRI-Unix        (415) 859-4576   Steve Kille       UCL           UCL-Netwiz@ISIE  (uk) (01)387-7050   Peter Kirstein    UCL           PKirstein@ISIA   (uk) (01)387-7050   Bill Tuck         UCL           UKSAT@ISIE       (uk) (01)387-7050Postel                                                          [Page 6]