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From: smith@umn-cs.UUCP (Richard Smith)
Newsgroups: net.dcom
Subject: Re: XON/XOFF as flow control? - (nf)
Message-ID: <358@umn-cs.UUCP>
Date: Sun, 13-Nov-83 21:01:19 EST
Article-I.D.: umn-cs.358
Posted: Sun Nov 13 21:01:19 1983
Date-Received: Tue, 15-Nov-83 06:12:44 EST
Sender: notes@umn-cs.UUCP
Organization: Computer Science Dept., U of Minn, Mpls, MN
Lines: 21

#R:umcp-cs:-363600:umn-cs:1600005:000:831
umn-cs!smith    Nov 13 10:09:00 1983

Re: 32 character input buffer.

   Yes, it IS an incredibly small amount.  Again, the old Arpanet TIPs
had terminal buffers of about that size.  This was never a problem except
with IBM terminals (i.e. 2741's) since REAL terminals used to all work
a character at a time.  The small buffers worked adequately because
of (1) appropriate network-level flow control and (2) fairly fast transmission
even across multiple network nodes.  Troubles started to appear when
people started hanging micros and bubble-terminals off of TIPs.  The
'solution' was to implement local Xon/Xoff.
  Why were the buffers so small?  Well, you had to fit too much into 32kb
of memory and if you had 63 terminals on your TIP, there just wasn't enough
memory to give everyone their own 1k buffer.

Rick.
[smith.umn-cs@CSNet-Relay]
 [...ihnp4!umn-cs!smith]