2.3 Modem Configuration
2.3.1 Basic async configuration—modem preparation

A modem can be configured in many different ways to work with a router. The Figure shows that a modem can be manually configured. This is done by sending attention (AT) commands to the modem. Alternatively, you may have the router automatically discover and configure the modem or you may specify which modem configuration commands the router sends to the modem. All these configuration methods are explored in greater detail in the following sections.