[ih] Statistical multiplexing

[John Gilmore]

> When was statistical multiplexing invented?

The first product I know of that included it was called a Smart/Mux.
One of my early employers, Scientific Time Sharing Corp. in Bethesda,
which ran an IBM mainframe running APL.  They used pairs of these to
compress the traffic of modem banks in remote cities (typically 300 baud
modems carrying 134.5bps printing Selectric terminal traffic, often
dialed in to with with acoustic couplers).  This was in about 1973.

I'd look for ads in old magazines like Datamation or Computerworld.
Here's an article in Computerworld of August 28, 1974, page 19, complete
with typos:

  https://archive.org/details/computerworld8275unse9/page/n17/mode/2up/search/%22smart+mux%22?q=%22smart+mux%22

  "DCA's Smart/Mux Has Bit/Sec Detection

  Atlanta - Digital Communications Associates, Inc. has added an
  intelligent remote multiplexer to its line of programmable front ends
  and concentrators.

  Thy Smart/Mux offers automatic bit/sec rate detection for 10-, 15- and
  30 char./sec terminals; complete character transparency; and error
  detection/retransmission, according to the firm.

  The multiplexer can transmit data from up to 32 interactive mixed-
  speed terminals over a 2,400 bit/sec synchronous link to the head-end
  multiplexer, and dial backup capability is provided, a spokesman
  noted.

  Smart/mux options include a remote line printer, card readers, full-
  and half-duplex 1,200 bit/sec terminal support, and support for IBM
  2780 remote job entry terminals.

  A host-end Smart/Mux can handle up to six remote-and multiplexers,
  the firm stated.  A typical system with 24 ports costs $18,400.

  Delivery is 60 days from the firm at 2801 Clearview Place, Suite 400,
  30340."

Hmm, it looks like IDG donated a complete set of Computerworld's and
funded their scanning by the Internet Archive!  Now there's some history...

Here's some brief info about the company:

  https://en.wikipedia.org/wiki/Digital_Communications_Associates

That page led me to this very interesting history of computer
communications by Jim Pelkey, from 85 interviews he also made available,
here:

  http://www.historyofcomputercommunications.info/

	John