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Configuring high-speed dialup


  www.kempston.net/solaris/ www.kempston.org/solaris/
  -------------------------
   This page contains detailed step-by-step instructions to configure Solaris 7 and Solaris 8 for high-speed dial-out and dial-in using V90 modems. It shows how to use Solaris to dialup and connect to a remote system with the Solaris system acting as a terninal on the remote system. It also shows how to configure Solaris to answer an incoming telephone call and provide terminal access to the calling system. It doesn't cover connecting a Solaris system to an ISP; this is a special form of dial-out and is covered in Configuring PPP on Solaris to connect to an ISP. It also doesn't cover configuring a Solaris system as a PPP server, accepting incoming PPP connections; this is covered in Configuring PPP dial-in on Solaris but this page is a prerequisite before configuring a PPP server.
  
   What this page does cover is using Solaris to dialup a remote system and run a terminal session on that remote system. It also covers the reverse scenario: allowing remote systems to dialup your Solaris system and run terminal sessions on it.
  
   Why would you want to do this? You may want to use your Solaris system to connect to a BBS, for example, or to any remote system which allows terminal-mode dial in access. Or you may want to configure your Solaris system at the office to give your customers dial in access or to enable you to connect to it from a Windows PC at home.
  
   Important Notes
  
   The instructions assume that your modem is external and attached to one of the two standard serial ports. Note that you must have a real modem; monstrosities known as WinModems are of no use whatsoever with unix. Unfortnately, I have no experience of using internal modems with Solaris and there may be additional configuration issues with these. I'm not able to advise about issues with internal modems but there's some useful advice at Celeste Stokely's Web pages and especially in her Tutorial on Solaris 2.x Modems & Terminals. Celeste's pages cover the configuration of modems in very much more detail than is offered here and are highly recommended for further reading. This page is intended to provide a simple, step-by-step procedure which should work for most people.
  
   Now for the instructions. No unix knowledge is assumed, other than the ability to edit files using a text editor.
  -------------------------------------------------------
   Configuring Solaris for high-speed dial out
   Please note that you must be logged in as root while implementing these instructions.
   These instructions describe how to configure Solaris and your modem for dial-out to a remote computer. Implement these instructions first, even if you want to configure your system for dial in access.
   1. Configure your serial port for dial out
   Start admintool under CDE:
   # admintool &
   Select the Browse menu and then Serial Ports from the drop-down list. Click on the line starting a if your modem is attached to the first serial port or on the line starting b if your modem is connected to the second serial port. Select the Edit menu and then Modify from the drop-down list.
   Change the following fields:
   Template: Modem - Dial out Only Baud Rate: 9600
   Cick on OK and close admintool.
   2. Test communication with the modem
   The unix command "tip" is used to communicate with a modem. If you're interested in the gory detail, the manual page for this command can be displayed by typing:
   # man tip
   If your modem is attached to the first serial port:
   # tip /dev/cua/a
   If your modem is attached to the second serial port:
   # tip /dev/cua/b
   and the command should respond:
   connected
   If it responds:
   All ports busy
   it means either that your serial port is configured incorrectly, perhaps for dial in instead of dial out, or that there is a more fundamental problem in communicating with the port. In this case, have a look at Celeste Stokely's Tutorial on Solaris 2.x Modems & Terminals which contains a wealth of useful information about modems.
   Type:
   ATZ
   and the modem should respond:
   OK
   If there's no response from the modem, check that you're using a straight-through cable with pin 2 at one end connected to pin 2 at the other end, pin 3 to pin 3 and so on. A "null-modem" or cross-over cable, designed for use with a terminal, will not work.
   Type:
   ATI4
   Most modems respond to this command by reporting their current settings. If this doesn't work, try AT&v, ATL5, ATL6, ATL7 or AT*c. If all else fails, consult your modem manual. When using a 3COM USR V90 modem, it responds:
  
   U.S. Robotics 56K Message Settings...
  
   B0 E1 F1 L2 M1 Q0 V1 X4 Y0
   SPEED=300 PARITY=N WORDLEN=8
   DIAL=TONE OFF LINE
  
   &A1 &B1 &C1 &D2 &H1 &I0 &K1
   &M4 &N0 &P0 &R2 &S0 &T5 &U0 &Y1
   ...
   Note that the actual speed at which Solaris is communicating with the modem is only 300 baud, or 30 characters per second, despite the speed having been set using admintool to be 9600. The reason for this is that tip defaults to a speed of 300 baud and we'll fix this in the next step.
  
   Close tip by typing "ENTER key, tilde, full stop" as three key strokes:
  
   ~.
   3. Set the modem DTE speed
   Edit the file /etc/remote and insert a line at the start of this file reading: modem:dv=/dev/cua/a:br#115200
   if your modem is attached to the first serial port, or: modem:dv=/dev/cua/b:br#115200
   if your modem is attached to the second serial port.
   This enables us to communicate with the modem at a speed of 115200 bits per second. It's important to understand that there are two speeds to be considered in modem communication. There's the speed at which the host computer talks to a connected modem and this is known as the Data Terminal Equipment or DTE speed. There's also the speed at which the modem transmits and receives data across the telphone line and this is known as the Data Communication Equipment or DCE speed. A 56K or V90 modem is capable of a DCE speed of up to 56K, although this is unlikely to be achieved in practice. Data sent down a telephone connection is often compressed with the receiving modem uncompressing the data before sending it to the host computer. So a modem to modem speed (DCE) of 56K could result in a modem to computer speed (DTE) well in excess of 56K. For this reason, the DTE speed should be set at least 50% higher than the maximum DCE speed and a DTE speed of 115200 is recommended for use with 56K modems.
   However, not all Sun hardware is capable of talking to a serial port at this speed. If you have a Sun Ultra 5 or better, or an Intel P90 or better, your system should be able to sustain a DTE speed of 115200. If you have an older Sun system, you may well not be able to drive a V90 modem at its maximum speed and will need to experiment to find the highest DTE speed that your hardware supports. If 115200 doesn't work, try specifying 38400, 19200 or 9600 in the line in /etc/remote.
   4. Test high-speed communication with the modem
   Try the tip test again, this time specifying the name of the new entry in /etc/remote as a parameter to tip and you should be rewarded with a high-speed connection to the modem:
  
   # t
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