PPP

This section is a quick-start guide to setting up PPP on Debian. If it turns out that you need more details, see the excellent |PPP HOWTO| from the Linux Documentation Project. The HOWTO goes into much more detail if you're interested or have unique needs.

Introduction

If you connect to the Internet over a phone line, you'll want to use PPP (Point-to-Point Protocol). This is the standard connection method offered by ISPs (Internet service providers). In addition to using PPP to dial your ISP, you can have your computer listen for incoming connections - this lets you dial your computer from a remote location.

Preparation

Configuring PPP on Debian GNU/Linux is straightforward once you have all the information you'll need. Debian makes things even easier with its simple configuration tools.

Before you start, be sure you have all the information provided by your ISP. This might include:

• Username or login
• Password
• Your static IP (Internet Protocol) address, if any (these look like 209.81.8.242). This information isn't needed for most ISPs.
• Bitmask (this will look something like 255.255.255.248). This information isn't needed for most ISPs.
• The IP addresses of your ISP's name servers (or DNS).
• Any special login procedure required by the ISP.

Next, you'll want to investigate your hardware setup: whether your modem works with GNU/Linux and which serial port it's connected to.

A simple rule determines whether your modem will work. If it's a ``winmodem'' or ``host-based modem,'' it won't work. These modems are cheap because they have very little functionality, and they require the computer to make up for their shortcomings. Unfortunately, this means they are complex to program, and manufacturers generally do not make the specifications available for developers.

If you have a modem with its own on-board circuitry or an external modem, you should have no trouble at all.

On GNU/Linux systems, the serial ports are referred to as /dev/ttyS0, /dev/ttyS1, and so on. Your modem is almost certainly connected to either port 0 or port 1, equivalent to COM1: and COM2: under Windows. If you don't know which your modem is connected to, run the program wvdialconf to try to detect it (see below); otherwise, just try both and see which works.

If you want to talk to your modem or dial your ISP without using PPP, you can use the minicom program. You may need to install the minicom package to make the program available.

The Easy Way: wvdial

The simplest way to get PPP running is with the wvdial program. It makes some reasonable guesses and tries to set things up for you. If it works, you're in luck. If it guesses wrong, you'll have to do things manually.

Be sure you have the following packages installed:

• ppp
• ppp-pam
• wvdial

When you install the wvdial package, you may be given the opportunity to configure it. Otherwise, to set up wvdial, follow these simple steps:

Log in as root, using su (as described in an earlier chapter).

touch /etc/wvdial.conf

touch will create the following file if the file doesn't exist; the configuration program requires an existing file.

wvdialconf /etc/wvdial.conf

This means you're creating a configuration file, /etc/wvdial.conf.

Answer any questions that appear on the screen. wvdialconf will also scan for your modem and tell you which serial port it's on; you may want to make a note of this for future reference.