From: utzoo!decvax!cca!mo@LBL-UNIX@sri-unix
Newsgroups: net.unix-wizards
Title: Re: Very Distant Host support under 4.1bsd Unix.
Article-I.D.: sri-unix.3199
Posted: Fri Sep 10 01:08:17 1982
Received: Fri Sep 10 06:59:17 1982

From: mo at LBL-UNIX (Mike O'Dell [system])
Date: 8 Sep 1982 09:43:47-PDT
With all due respect for the people that did the VDH back in the
Dark Ages, the VDH is famous for not working very well.  They
have been the cause of premature retirement for more than one
good ARPAnet software support person. There are persistant
rumors that Greg Noel down at NOSC may be working on a VDH
driver for 4.1a, but if he gives up, noone would blame him.  The best
thing to do, if your IMP must be remote from you, is to get a pair
of ECU-II's from ACC.  The Error Control Units connect to modems
between the pair, and to the host, it looks like a local IMP interface,
and to the IMP, it looks like a local host interface.  ECU's are not
perfect, and if you have a really rotten phone line between them,
you will have grief, but not nearly as much as with a VDH.  The other
alternative would be to do an HDH driver, which would actually be
doing the world a large service.  But I am somewhat curious about
your comment about "do I really need a C30?"  If you don't
have one, who does??  I have been assuming from your questions that
you will be remote from some other IMP.  Somewhere the must be an IMP
HOST PORT to which your machine is attached.

	-Mike