From the Internet Service Provider:
The dialup phone number
The Login Name to use for the PPP connection
The account password
The IP address of the ISP's Name Server
The dialup number is not the same number you use to contact tech support or the front office of your ISP. This is the number that they will provide for connecting to their machine. The ISP will also provide you with a Login Name (possibly of your choosing) and a password to start with. This password should be changed to something else at the first opportunity. The Name Server address will also be provided by the ISP upon request. This address allows the system to convert domain names into IP addresses, so that you will only need to remember something like ftp.debian.org, instead of 130.207.7.21.
Debian now provides a utility called pppconfig, which is used during the installation to configure the PPP connection. This program uses the ``peer method'' of configuring the ppp daemon. This allows the configuration of several PPP connections to satisfy the various ISP or work and school related connections. For each peer you will need the previously discussed information about that connection. pppconfig will let you construct a new peer configuration as well as editing an existing peer. This script constructs a peer based options file linked with a chat script for that peer along with a possible papsecrets file. These files allow the PPP daemon to make a proper connection to the designated peer.
In addition to the configuration script there are two scripts, pon and poff provided for starting your various peer connections. To start the ppp connection simply enter the command pon <peer>, while poff will shut down the connection when you are finished with it.
You should now have all the information you need to begin the installation.