Both external and internal modems can be used for PPP connections.
The command set used in a modem is normally described in the modem documentation. The commands are used to reset and initialize the modem, and to tell the modem to dial the telephone number of the remote system. Each modem model has to be defined before it can be used with a PPP connection profile because different modem models have different initialization command strings. If it is an internal modem then the modem strings are already defined for their use.
The iSeries™ server has many modem models predefined, but new models can be defined through iSeries Navigator. An existing definition can be used as a base for the new type to be defined. If you are not sure what commands your modem is using, or if you do not have access to the modem documentation, start with the Generic Hayes modem definition. The predefined shipped definitions cannot be changed. However, additional commands can be added to the existing initialization command or dial string.
You can use the electronic customer support (ECS) modem that is shipped with the iSeries server to establish PPP connections. On older systems, the ECS modem was an IBM® 7852-400 external modem. On newer systems, the 2771, 2793, or any of the other supported Internal modems may be used as the ECS modem.