Tymnet

1 definition found

From The Free On-line Dictionary of Computing (27 SEP 03) [foldoc]:

  TYMNET
       
           A United States-wide commercial computer
          network, created by {Tymshare, Inc.} some time before 1970,
          and used for {remote login} and file transfer.  The network
          public went live in November 1971.


       
          In its original implementation, it consisted of fairly simple
          circuit-oriented {nodes}, whose circuits were created by
          central network supervisors writing into the appropriate
          nodes' "permuter tables".  The supervisors also performed
          login validations as well as circuit management.  Circuits
          were character oriented and the network was oriented toward
          interactive character-by-character {full-duplex}
          communications circuits.
       
          The network had more than one supervisor running, but only one
          was active, the others being put to sleep with "sleeping pill"
          messages.  If the active supervisor went down, all the others
          would wake up and battle for control of the network.  After
          the battle, the supervisor with the highest pre-set priority
          would dominate, and the network would then again be controlled
          by only one supervisor.  (During the takeover battle, the net
          consisted of subsets of itself across which new circuits could
          not be built).  Existing circuits were not affected by
          supervisor switches.
       
          There was a clever scheme to switch the echoing function
          between the local node and the host based on whether or not a
          special character had been typed by the user.  Data transfers
          were also possible via "auxiliary circuits".
       
          The Tymshare hosts (which ran customer code) were {SDS 940},
          {DEC} {PDP-10}, and eventually {IBM 370} computers.  {Xerox}
          {XDS 940} might have been used if Xerox, who bought the design
          for the SDS 940 from Scientific Data Systems, had ever built
          any.
       
          The switches were originally {Varian Data Machines} 620i.  The
          {Interdata 8/32} was never used because the performance was
          disappointing.  The TYMNET Engine, based loosely on the
          Interdata 7/32, was developed instead to replace the Varian
          620i.  in the early 1990s, newer "Turbo" nodes based on the
          {Motorola 68000} began to replace the 7/32s.  These were later
          replaced with {SPARC}s.
       
          PDP-10s supported (and still do in 1999) cross-platform
          development and billing.
       
          {Tymshare, Inc.} originally wrote and implemented TYMNET to
          provide nationwide access for their {time-sharing} customers.
       
          La Roy Tymes booted up the public TYMNET in November of 1971
          and, as of March 2002, it had been running ever since without
          a single system crash.
       
          TYMNET was the largest commercial network in the United States
          in its heyday, with nodes in every major US city and a few
          overseas as well.  Tymshare acquired a French subsidiary,
          {SLIGOS}, and had TYMNET nodes in Paris, France.
       
          Tymshare sold the TYMNET network software to {TRW}, who
          created their own private network (which was not called
          TYMNET).  In about 1979, TYMNET Inc. was spun off from
          Tymshare, Inc. to continue administration and development of
          the network.
       
          TYMNET outlived its parent company Tymshare and was acquired
          by {MCI}.  As of May 1994 they still ran three {DEC KL-10}s
          under {TYMCOM-X}, although they planned to decommission them
          soon.
       
          The original creators of TYMNET included: Ann Hardy, Norm
          Hardy, Bill Frantz.  La Roy Tymes (who always insisted that
          his name was NOT the source of the name) wrote the first
          supervisor which ran on the 940.  Joe Rinde made many
          significant technical and marketing contributions.  La Roy
          wrote most of the code of the network proper.  Several others
          wrote code in support of development and administration.  Just
          recently (1999) La Roy, on contract, wrote a version of the
          supervisor to run on {SPARC} hardware.
       
          The name TYMNET was suggested by Vigril Swearingen in a weekly
          meeting between Tymshare technical and marketing staff in
          about 1970.
       
          {(http://cap-lore.com/ETH.html)}.
       
          [E-mail from La Roy Tymes]
       
          (2002-11-26)