Path: utzoo!mnetor!uunet!steinmetz!davidsen
From: davidsen@steinmetz.steinmetz.ge.com (William E. Davidsen Jr)
Newsgroups: comp.dcom.modems
Subject: Re: Avatex 1200 Problems
Message-ID: <10227@steinmetz.steinmetz.ge.com>
Date: 4 Apr 88 15:11:33 GMT
References: <2485@bsu-cs.UUCP> <162@turnkey.TCC.COM>
Reply-To: davidsen@kbsvax.steinmetz.UUCP (William E. Davidsen Jr)
Organization: General Electric CRD, Schenectady, NY
Lines: 30

In article <162@turnkey.TCC.COM> jack@turnkey.TCC.COM (Jack F. Vogel) writes:

>James,
>	I suspect that your problem originates in the fact that the BBS system
>has changed over to Multitech. Our system uses 2 Multitech 224E's and I noticed
>a problem connecting to certain systems. The origin of the problem is probably
>the MNP protocol. In addition to the normal signal there is some data sent out
>by the multitech to determine whether the other modem does MNP or not. On 

Someone feel free to correct me, but I believe the MNP startup is sent
only by the calling modem. I have had to disable MNP on some outgoing
calls, but have never (yet) seen a problem incoming. However, this could
happen if the sysop has set the MNP mode to "force" rather than "auto."
The auto mode is the one intended for access by all modems, while force
mode is for connections so bad that protocol negotiation fails.

When calling into a non-MNP UNIX system with an MNP modem, after the
connection takes place, the MNP modem sends a burst which says "Hey!
Would ya like to talk MNP?" If the remote system is fast enough to have
asked for a login at that point, it will accecpt the noise as an unknown
UID  and the connection will usually get completely out of sync. With a
human on the other end it is often possible to recover.

I think that asking to disable MNP might defeat the reason for buying
them, but certainly asking for auto mode (AT&E=1) is reasonable. Let us
know what happens.
-- 
	bill davidsen		(wedu@ge-crd.arpa)
  {uunet | philabs | seismo}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me