Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!utah-gr!haas From: haas@utah-gr.UUCP (Walt Haas) Newsgroups: comp.protocols.tcp-ip Subject: Re: Milking machines Message-ID: <2874@utah-gr.UUCP> Date: 23 Sep 88 21:20:45 GMT Organization: University of Utah CS Dept Lines: 39 Roger Fajman (RAF@NIHCU.BITNET) writes: > ...We currently have a Bridge CS/1 with 32 ports that is hooked up to our > IBM mainframe as a milking machine... Our biggest complaint about the > Bridge CS/1 is that it does not negotiate the Telnet option correctly. It > says that it will echo and then expects the host to do it. The problem is > that our host does not echo, so the user must manually turn on echoing at > their end... We received from 3com/Bridge a model CS/1 running release 20000 of their TCP software for evaluation. When I TELNET to it from cs.utah.edu, a VAX 8600 running 4.3 BSD, the following actual TELNET parameter negotiation occurs (as observed with an Ethernet monitor): CS/1: WILL SUPPRESS-GO-AHEAD DO SUPPRESS-GO-AHEAD WILL TRANSMIT-BINARY DO TRANSMIT-BINARY WILL ECHO VAX: DO SUPPRESS-GO-AHEAD WILL TERMINAL-TYPE CS/1: DONT TERMINAL-TYPE VAX: WILL SUPPRESS-GO-AHEAD DONT TRANSMIT-BINARY WONT TRANSMIT-BINARY DO ECHO VAX: WONT TERMINAL-TYPE The TELNET ECHO option negotiated here indicates that the CS/1 end of the connection will be responsible for any necessary echoing of keystrokes received from the VAX. In our configuration, the host which is being milked by the CS/1 (a Zenith Z-LAN 500 NCU) does the actual echoing, which is exactly as we want it. If however we were milking a host which was not able to echo for some reason, then we would need to be able to tell the CS/1 to send WONT ECHO in the initial TELNET parameter negotiation, which would have the effect of forcing the VAX to echo. In my study of the User's Guide for the CS/1 I failed to find a way to get the CS/1 to do this (that doesn't mean the CS/1 *can't* do this, of course, just that I couldn't figure out the magic words :-). Cheers -- Walt Haas haas@cs.utah.ed utah-cs!haas