Path: utzoo!mnetor!uunet!steinmetz!davidsen
From: davidsen@steinmetz.steinmetz.UUCP (William E. Davidsen Jr)
Newsgroups: comp.dcom.modems
Subject: Re: YATB
Message-ID: <9920@steinmetz.steinmetz.UUCP>
Date: 14 Mar 88 16:52:48 GMT
References: <1849@mtunx.ATT.COM> <3830@umix.cc.umich.edu> <16750@pyramid.pyramid.com> <17965@oliveb.olivetti.com>
Reply-To: davidsen@crdos1.UUCP (bill davidsen)
Organization: General Electric CRD, Schenectady, NY
Lines: 20
Keywords: techdoc Telebit questions

In article <17965@oliveb.olivetti.com> jerry@oliveb.UUCP (Jerry Aguirre) writes:
| [...]
| The suggestion that full speed is possible with a window of 1 is
| ludicrous.  The modem would be able to send only 1 packet.  It would
| then have to wait for an ack before it could send another.  At a minimum
| that means 8 bytes of idle time for every 64 bytes received.  The line
| would be idle for 12% of the time.  Any time to process the incomming
| packet and generate the ACK would add to that.

  If the feed to the modem is at 19.2k, since the ack is generated at
the modem, and accepted at the modem, the two systems should be able to
drive the actual line at the maximum of 11-14k (depending on who's
figures you see).

  I completely agree that this is not a desirable thing from the
standpoint of interrupt overhead.
-- 
	bill davidsen		(wedu@ge-crd.arpa)
  {uunet | philabs | seismo}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me