4000 Router Series Interface Configuration Guide

Step Command Remarks

19. (Optional.) Set the intended

bandwidth for the

synchronous serial interface.

bandwidth bandwidth-value

By default, the expected

bandwidth (in kbps) is the interface

baud rate divided by 1000.

20. (Optional.) Restore the default

settings for the synchronous

serial interface.

default N/A

21. Bring up the synchronous

serial interface.

undo shutdown

By default, a synchronous serial

interface is up.

Displaying and maintaining serial interfaces

Execute display commands in any view and reset commands in user view.

Task Command

Display information about the

specified serial interfaces.

display interface [ serial ] [ brief [ down ] ]

display interface [ serial [ interface-number ] ] [ brief [ description ] ]

display interface [ async ] [ brief [ down ] ]

display interface [ async [ interface-number ] ] [ brief [ description ] ]

Clear statistics on a specified serial

interface.

reset counters interface [ serial [ interface-number ] ]

reset counters interface [ async [ interface-number ] ]

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, might deviate somewhat depending on the line quality, PBX

performance, connection protocol, and other elements.