From owner-freebsd-questions  Mon Jun 12 16:38:01 1995
Return-Path: questions-owner
Received: (from majordom@localhost)
          by freefall.cdrom.com (8.6.10/8.6.6) id QAA08297
          for questions-outgoing; Mon, 12 Jun 1995 16:38:01 -0700
Received: from antares.aero.org (antares.aero.org [130.221.192.46])
          by freefall.cdrom.com (8.6.10/8.6.6) with SMTP id QAA08290
          for <freebsd-questions@freebsd.org>; Mon, 12 Jun 1995 16:37:59 -0700
Message-Id: <199506122337.QAA08290@freefall.cdrom.com>
Received: from anpiel.aero.org by antares.aero.org (4.1/AMS-1.0)
	id AA09820 for freebsd-questions@freebsd.org; Mon, 12 Jun 95 16:37:28 PDT
To: freebsd-questions@freebsd.org
Subject: ISDN connection: serial, or ethernet?
Date: Mon, 12 Jun 1995 16:37:11 -0700
From: "Mike O'Brien" <obrien@antares.aero.org>
Sender: questions-owner@freebsd.org
Precedence: bulk

	I'm considering installing an ISDN connection, and I'm trying to figure
out which of the two methods usually used in the U.S. would be better: an ISDN
'modem' that connects to a serial port, or something like the Ascend Pipeline 50 HX,
which connects to an Ethernet interface.

	Now, if I were back in the minicomputer world this would be a no-brainer.
Character interfaces are interrupt-per-character, at least potentially, though
of course with a 16550 silo, things aren't nearly this bad.  Ethernet interfaces
are DMA devices, resulting in a much lower load on the CPU.

	This, though, is the PC world.  I am quite prepared to believe that due
to vicious cost-cutting measures and generally brain-dead design, this MIGHT
not be true.  So, I'm asking for the REAL answer: which is the better type
of interface to go with?  And, if it's Ethernet, what are the more satisfactory
types of Ethernet interface to use?  I know I've seen a lot of traffic about
the 3C509, but whether that's because it's the most popular, or because it's
the most brain-dead, I don't know.

	Opinions, please?

Mike O'Brien