RFC 327 (rfc327) - Page 2 of 5

Data and File Transfer workshop notes

RFC 327          Data and File Transfer Workshop Notes        April 1972


   Richard Winter discussed the Datacomputer application.  The
   Datacomputer though usable from terminals directly will not be
   engineered for direct terminal users, but for use by programs.  In
   Datalanguage a user can define data and file structure, and also how
   the file/data is to be transferred.  Using the data language it is
   possible to transfer entire files, or only the relevant parts of
   files.  The following is an example of file transfer as currently
   envisioned in the Datacomputer.

          LOGIN  
          CREATE  
          CREATE  
          PORT   =  (for transfer to Datacomputer)
           =  (for transfer from Datacomputer)
          LOGOUT

   (CREATE statements are needed only when the description(s) required
   are not already on file at the Datacomputer.  A port description can
   specify a standard "external name", thus making a port statement
   optional also.  "External name" is to be a HOST-socket specification.
   The data transfer is to be in accordance with network data transfer
   standards.  The File and Port descriptions are to be in
   Datalanguage.)

   Alex McKenzie discussed the TIP user needs, describing the current
   capabilities and limitations of TIPs and TIP terminals.  TELNET
   format is the first choice of TIP users, followed by DTP using the
   indefinite bit stream mode.  There are two TIPs with magnetic tape
   systems which are capable of transferring data between them using the
   current DTP (RFC 264) in the descriptor count mode (utilizing
   sequence number option).

   Bob Braden discussed the RJS protocol and presented some data on RJS
   use.  NETRJS is 1% of CCN job load representing 2,000 jobs, 10,000
   sessions and 1,000 hours connect time in the last 5 months.  Average
   job input is of the order of 100,000 bits (400 cards), average job
   output is 700,000 bits (1,000 lines).  Large files have about 10
   million bits representing about 8-10 minutes of transmission time.
   The RJS protocol will be defined in a forthcoming document.

   Ray Tomlinson described the CPYNET system BBN is using to transfer
   files among TENEX systems.  CPYNET commands are ASCII strings with a
   fixed syntax.  The original connection is closed after a command is
   accepted, and data is transferred on a new connection using previous
   socket number, but with possibly a different byte size.  The data
   transfer rate achieved in CPYNET has been about 10 Kb/s.




Bhushan