BURKS 2/BURKS_AUG97.ISO/BURKS/LINUX/HOWTO/mini/pppisdn.txt

Internet Message Format | 1997-07-07 | 5KB

Date: Sat, 13 Apr 1996 20:15:17 -0700 (PDT)
From: Nobody <[e-mail]>
Subject: Serial ISDN using MLPPP

R Marc Phillips | Need and be abandoned.
[e-mail]| Hope and be denied.
Semi-Psychotic  | Love and be destroyed.
Mostly Confused | -me

This is a basic guide to using ppp over an external ISDN device.  As of
yet there are no drivers that I know of for ISDN cards readily available
in the USA.  This is a guide to ISDN over a serial port.

The first thing you'll need is PPP compiled on your linux system.  With
most releases of Linux Slackware, it is an option on recompiling and
sometimes installing.  If you don't have it you can get the latest BETA from:

ftp.funet.fi:/pub/Linux/BETA/ppp/ppp-2.2

Note that this is for later kernels (1.3.8x and above) for earlier kernels
you may want to look for ppp2.2.0d or e.  A search on www.yahoo.com for ppp
should yield something.

Once you have that installed and functional (you can usual see if it's
functional, if you're not sure, by just typing pppd at a prompt. You'll
then see a bunch of garbage start scrolling across your screen.  This
means you have it installed.  It'll time out in a minute or two or you
can go to another virtual terminal and kill the process.).

Now you'll want to make a pap-secrets file.  This is a file that simply
contains you username and password.  PAP stands for Password
Authentication Protocol which is a function of PPP and a required
component of MultilinkPPP as defined in the RFC documentation on
Multilink protocols:

http://www.cis.ohio-state.edu/htbin/rfc/rfc1356.html

I'd advise that you put this file in /etc/ppp and call it something like
pap or pap-secrets.  What you name it really doesn't matter.  The file
should have two lines in it.  The first line containing your username
and the second containing your password.

Once you've done that, you can try out a PPP connection.  The easiest way
would be to make a file called "pppfix" or something (again, it can be
called whatever you want).  Here is an example:

#!/bin/sh
pppd modem crtscts defaultroute +ua [path to pap file] connect 'chat \
ABORT BUSY ABORT ERROR "" AT[init string] OK ATD[ISP's Phone #] CONNECT' \
[your comm port] 115200

There are two parts to this, the pppd component and the chat component.

I've put anything that you need to decide upon in square brackets.  You
need to replace those with the appropriate information.  Say you made a
file in your /etc/ppp directory called "pap" that contains your username
and password.  You'd put in /etc/ppp/pap replacing "[path to pap file]."
For "[init string]" you'll want to put in the appropriate string for
MultilinkPPP (this will work equally as well for a modem, so if you want
to use your modem put in a string for it).  You can look in your manual
to find the appropriate string.  I'll give a few:

For a 3com impact put in: s71=1s80=1&d2
For a Bitsurfer put in: %a2=92@b0=2&d2
For a Bitsurfer Pro: %a2=92@b0=2@m2=p&d2
For an Adtran ISU express: s54=12&d2

Add whatever else you would normally for your box, but these are what is
necessary for MultilinkPPP plus the &d2 which will insure that your box
will hang up when you disconnect.  Some TA's have a hard time hanging up
without that &d2 (especially the Bitsurfer and Bitsurfer pro)

After the ATD you put in your ISP's ISDN phone number in replace of
"[ISP's Phone #]." (note that with the Bitsurfer and Bitsurfer pro it is
necessary to tell the TA to dial the same number twice seperated by an "&."
It is not necessary to put in an escape character).

Where you see "[your comm port]" you'll need to replace that with the
appropriate comm port. In most cases that will be /dev/cuaX where the X
is a number between 0 and 3.  0 being comm1 and 3 being comm4.

Now make the file executable by typing "chmod 755 <filename>" or
whatever you'd like the permissions to be (700 if you only want root to
have rights to it).  You'll want to also make sure that your pap file
is readible to whomever is running the pppd process so that it'll log in. To
run it you'd simply type the name of the file.

When you run this it should connect and then you can type "ifconfig" at
your prompt.  You should see that you have an "inet addr"  under "Link
encap: Point-Point Protocol" like so:

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Bcast:127.255.255.255  Mask:255.0.0.0
          UP BROADCAST LOOPBACK RUNNING  MTU:2000  Metric:1
          RX packets:132 errors:0 dropped:0 overruns:0
          TX packets:132 errors:0 dropped:0 overruns:0

ppp0      Link encap:Point-Point Protocol
          inet addr:204.31.114.199  P-t-P:163.179.20.26  Mask:255.255.255.0
          UP POINTOPOINT RUNNING  MTU:1500  Metric:1
          RX packets:47 errors:0 dropped:0 overruns:0
          TX packets:62 errors:0 dropped:0 overruns:0

To hang up, kill the process.  If you don't know how to do that type "man
ps" and then "man kill" and read.

Here's an example:

kill `ps -x | grep pppd | head -1 | cut -c2-5`

You should then write scripts to manage your ppp connections.

This is only one way to do it, there are others.  You can download some
scripts for this from the following ftp site:

ftp.netcom.com/ftp/pub/rm/rmarc/lnxstuff.zip

There's a readme file with it.  I didn't write these scripts and they are
not the ones I use.  They are nice for a beginner and do not use PAP so
you'll have to modify them if you want to do MultilinkPPP.


Have fun.