Date: Sat, 9 Aug 1997 17:35:56 +0100 (BST) From: Andrew Gordon <arg@arg1.demon.co.uk> To: "Julian H. Stacey" <jhs@freebsd.org> Cc: current@freebsd.org, isdn@muc.ditec.de Subject: Re: ISDN drivers/cards Message-ID: <Pine.BSF.3.91.970809170805.2939A-100000@server.arg.sj.co.uk> In-Reply-To: <199708052316.BAA01266@wall.jhs.no_domain>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, 6 Aug 1997, Julian H. Stacey wrote: > > steve@visint.co.uk writes: > > > I tried using bisdn, both with -current and 2.2.2, without much luck, > > > I'm > > in europe (england) > > I'm in Germany, FWIW a friend of mine (Barry S) who has developed a number > of isdn PC cards ( not supported by bisdn, far as I know, but described on > http://www.freebsd.org/~jhs/lion/ ) says nasty things about British Telecom's > isdn service implementation, in comparison with Deutsche Telekom's > implementation... maybe there is something different for you in the UK > (the developers are mostly based in Germany) ? I don't believe this is the case. While there are various deficiencies in BT's ISDN implementation, most of them relate to services that BT simply don't provide. The main issues which cause interoperability problems relate to the bearer-capabilities, higher-layer-compatibility and lower-layer-compatibility fields, but since BISDN doesn't implent V.120 or outgoing voice calls, these have no effect on BISDN. Note that there are several implementations of ISDN available in the UK, all claiming to offer EuroISDN: 1) BT's older offering, implemented via an IMUX unit on the front of a DASS2 connection to a System X or AXE10. Identified by the tall, rectangular NTE box on your wall. 2) BT's current offering, implemented as an imbedded linecard in System X exchanges. Identified by the smaller, curved front NTE. This theoretically offers the same service as the IMUX version, but I believe there are some differences since the call is no longer mangled by the protocol conversion to DASS2 (I believe that this is where the BC/HLC/LLC corruption occurs). 3) BT's new offering, not yet available, providing "Full ETSI call control". Documentation of this (incuding the differences from the current offering) are available in SIN261, available from http://www1.btwebworld.com/sinet/ . I believe this is just a software upgrade from 2) above; I'm not sure what happens to people in areas served from AXE10 exchanges - maybe there will be a linecard for AXE10 too. 4) Various solutions offered by Cable TV companies. My local cableco serves this area from a Nortel DMS switch, but apparently Nortel's software for EuroISDN was too expensive, so they are providing ISDN from their smaller Nokia switch which provides telephone service to outlying villages. Other cablecos have Nortel and System X switches - and possibly others too. I have used BISDN with both BT lines (type 2 above) and a cableco line from a Nokia switch. I have had no interworking problems whatever, apart from when the cableco first introduced their service and the Nokia switch was generating completely invalid protocol and generally not working at all; unfortunately, they fixed it before I had a chance to debug why BISDN was crashing under this abuse. It's just possible that IMUX lines might cause problems (I haven't had the chance to test BISDN with one), but given the nature of the differences I would be very surprised. > > and although bisdn connects and works most of the time > > it did have a nasty habit of just halting the machine completely. > > Never has halted for me, but then my isdn machine runs lighter perhaps > than yours (just does net, not X11 & keyboard driven other stuff, that I run on > another ethernet'd box). I have seen problems with the PPP patches installed, but not otherwise. > > It was a pain to > > install Again, sounds like using PPP. The base BISDN install is trivial - you put up the Install.FreeBSD-2.1 in one xterm, cut and paste the instructions into another xterm, and you are installed in about 1 minute flat. PPP is much more of a fiddle. > > and IMHO is a total mess. > > I wouldn't know about the code stylistic quality, I've not looked, > I've only hacked one trivial tiny morsel (to add bell on connect/disconnect). Again, the base BISDN is quite sound, but the PPP patches are just a quick hack - as acknowledged by those involved in producing them. Given that BISDN is being re-written, there is little motivation to do further work on PPP for the old version. It does, however, work well if used carefully. > > Well, just wanted to say that in case someone suggests that we should all > > be using bisdn. Because IMHO, it sucks, and really shouldn't be used as a > > base for future code either. (except as a bad example.) Well, you are intitled to your opinion, but expressing it in the form of general abuse (as opposed to specific criticism of techniques used) is not at all helpful.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.3.91.970809170805.2939A-100000>