sl@van-bc.wimsey.bc.ca (Stuart Lynne) (10/03/90)
Several of my users have suggested replacing my aging 2400 bps dialup modems with MNP-5 2400 bps modems (which apparantly are not the expensive anymore, I can get a good price on the Everex 2400/9600 modems). These dialup lines have about a 50% usage rate. About 2/3 uucico and 1/3 interactive. Any comments on the use of MNP-5 modems with Unix for dialup purposes? Is the interactive usage really all that much better? Are there any special setup's to keep /etc/getty happy? How well does uucp work over an MNP-5 connection? Any special setup's suggested to keep uucico happy? Does anyone have a dialMNP.c for SCO Xenix? How compatible is MNP-5? If I get ye-old 2400 Hayes clone type modem with MNP-5 will "any" MNP-5 modem be able to connect in "auto-reliable" mode? Will such popular modems as the HST and Hayes "V" type modems be able to connect? Should the speed we talk to the modem at (from /etc/getty and uucico) be locked at 4800bps or 9600bps or ?? If *you* had four lines to switch over what would you do? (We already have other lines dedicated to PEP users so that's not a consideration.) Thanks. Postings monitored, email welcome. I'll summarize if there is anything significant to report. -- Stuart Lynne Unifax Communications Inc. ...!van-bc!sl 604-937-7532(voice) sl@wimsey.bc.ca
root@zswamp.fidonet.org (Geoffrey Welsh) (10/04/90)
> From: sl@van-bc.wimsey.bc.ca (Stuart Lynne) > Message-ID: <2320@van-bc.wimsey.bc.ca> > > Any comments on the use of MNP-5 modems with Unix for dialup purposes? > Is the interactive usage really all that much better? The fact that the connection is now noise-free is important as far as I'm concerned. I hate it when, in a vi session, line noise spews two lines of crap into the text, ESCapes to command mode, backs up a pararaph, and then deletes to top of text. undo only goes back one command, so I can't easily repair the damage. This simply isn't a concern with MNP. If the line noise gets so bad that no data gets through, the connection is broken and I simply have to recover the working text from the saved buffer. On the other hand, MNP (especially the higher levels) can introduce delays in passing keytrokes to the host and receiving the echo. Combined with the buffers that inevitably come with MNP modems, this can annoy someone who's used to 'instant' response. > How compatible is MNP-5? If I get ye-old 2400 Hayes clone type > modem with MNP-5 will "any" MNP-5 modem be able to connect in > "auto-reliable" mode? Will such popular modems as the HST and > Hayes "V" type modems be able to connect? Beware. Some early 9600+ bps modems (Telebit Trailblazer, Hayes V-series with X.25 or LAP-B only) don't support MNP. Any modem that says "MNP" or "V.42" should provide an error-free connection to any other modem with either of those markings on it. > Should the speed we talk to the modem at (from /etc/getty and > uucico) be locked at 4800bps or 9600bps or ?? Locked port speeds usually give the best performance. -- UUCP: watmath!xenitec!zswamp!geoff | 602-66 Mooregate Crescent Internet: geoff@zswamp.fidonet.org | Kitchener, Ontario FidoNet: SYSOP, 1:221/171 | N2M 5E6 CANADA Data: (519) 742-8939 | (519) 741-9553 "Experience talks... and talks... and talks..."
sl@van-bc.wimsey.bc.ca (Stuart Lynne) (10/04/90)
In article <2320@van-bc.wimsey.bc.ca>, sl@van-bc.wimsey.bc.ca (Stuart Lynne) writes: > Several of my users have suggested replacing my aging 2400 bps dialup modems > with MNP-5 2400 bps modems (which apparantly are not the expensive anymore, > How well does uucp work over an MNP-5 connection? Any special setup's > suggested to keep uucico happy? Does anyone have a dialMNP.c for SCO Xenix? Well I thought I might as well bite the bullet and do some testing. Setup two MNP-5 2400 bps modems up, with DTE/DCE speeds locked at 4800. The file being transfered was picked at random from set of compressed news batches. I then connected in MNP-Reliable with compression, MNP-Reliable without compression and then without MNP. The results are 158, 206 and 219 bps respectively. So for uucico and compressed news any use of MNP is not efficent. It might be possible that MNP Reliable mode with no compression might be better over noisy lines. van-bc!root M (10/4-0:28:41) (C,8378,1) [ttyaF] -> 251369 / 1589.440 secs, 158 bytes/sec van-bc!root M (10/4-0:53:26) (C,9147,1) [ttyaF] -> 251369 / 1215.940 secs, 206 bytes/sec van-bc!root M (10/4-1:19:21) (C,9617,1) [ttyaJ] -> 251369 / 1146.640 secs, 219 bytes/sec So it would appear that MNP-5 modems will have to be justified on the basis of the interactive users, and will have to not interfere with normal 2400 bps connections (rumor has it that the MNP tones might confuse some 2400 bps modems trying to connect). -- Stuart Lynne Unifax Communications Inc. ...!van-bc!sl 604-937-7532(voice) sl@wimsey.bc.ca
vernon@hpcvaac.cv.hp.com (Vernon King) (10/04/90)
We are presently using 2400baud modems with mnp5. Be sure to turn on flow
control with mnp5. We set our data pbx to 9600 baud and set the terminals at
home to 4800baud. This allows access to our fixed 9600baud ports at work. You
must turn flexible baud adjust on. You can set both sides to 9600 but with
mnp5 (2 to 1 compresion) you will end up with a very jerky screen at home.
Mnp 7 or v42bis could allow you to set both ends at 9600 but I have not played
with either of these schemes. If you are a HP3000 user be sure to buy a modem
with enq-ack support or you will be forced to logon your 3000 as a vt100 and
you will loose certain funtions. If you are using a serial to lan conversion
box such as a cisco you will need to turn flowcontrol on if it does not default
to on. Hardware flowcontrol will substitute for above xon-xoff if thats what
you choose to run. Remember if data is compressed thruput will not rise above
a normal 2400baud modem but for text vi or notes it works great.
Vernondatri@convex.com (Anthony A. Datri) (10/05/90)
> Beware. Some early 9600+ bps modems (Telebit Trailblazer, Hayes >V-series with X.25 or LAP-B only) don't support MNP. Any modem that >says "MNP" or "V.42" should provide an error-free connection to any Well, to be accurate, the TB (with 4.0 proms, at least) will do MNP3 at slow speeds. I believe that the 5.0 proms will do MNP5. PEP connections have always been error-free. --