R2511-HP MSR Router Series Interface Configuration Guide(V5)

Configuring an AM interface

Overview

Analog modem (AM) interfaces bring services provided by asynchronous serial interfaces and analog

modems together. Most of the configuration commands used on asynchronous serial interfaces and

modems can be directly used on AM interfaces. When you configure an AM interface, you can treat it

as a special asynchronous serial interface.

AM interfaces provide dial-in and dial-out services for analog dial-up users.

Theoretically, if the peer (usually an ISP) uses a digital modem, the AM interface can establish connection

with the V.90 Modem standard to provide downstream rates up to 56 kbps and upstream rates up to

33.6 kbps. If the peer (usually a common user) uses an analog modem (or an AM interface), the AM

interface can establish connection with the V.34 Modem standard to provide rates (both downstream

and upstream) up to 33.6 kbps.

The real rate of an AM interface, however, may deviate somewhat depending on the line quality, PBX

performance, connection protocol, and other elements.

Configuration procedure

To Configure an AM interface:

Step Command Remarks

1. Enter system view.

system-view N/A

2. Enter AM interface view.

interface analogmodem number N/A

3. Set the coding format of the

modem.

country-code area-name

Optional.

united-states by default.

4. Set asynchronous interface

properties.

See "Hardware compatibility." Optional.

To set the baud rate for an AM interface, use the speed command in user-interface view. For more

information, see Fundamentals Configuration Guide.

The configuration of AM interface is similar to that of asynchronous interface and modem, except that an

AM interface does not support the modem auto-answer and the baudrate commands. For more

information about modem configuration, see Layer 2—WAN Configuration Guide.

Configure PPP, DCC, IP address, firewall, and backup center on the AM interface if the network requires.