Technical Documentation

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• Example: Configuring Modem Connections (NSM Procedure)     

• Related Topics
• Example: Creating Modem Settings (NSM Procedure)
• Example: Creating ISP Connection Settings (NSM Procedure)
• Interface Failover in ScreenOS Devices

Example: Configuring Modem Connections (NSM Procedure)

The modem is only available for some security devices. Use the Modem option to configure the security device for operation with an external modem. You can connect an external modem to the RS-232 serial port on certain security devices to enable the device to establish a PPP connection to an ISP. This provides a backup serial interface for traffic to the Untrust zone if there is a failure on the connection through the primary interface.

You can configure the parameters for the serial link as described in Table 1.

Table 1: Parameters for Serial Link

Parameters	Range Value
Speed (BPS)	The maximum baud rate for the serial link (the default rate is 115,200 bps).
Timeout	The maximum amount of time that the serial link can be idle before ScreenOS automatically disconnects the modem (the default is 10 minutes).
Retry Number	The number of times ScreenOS retries the dial-up connection if the line is busy or there is no response (the default is 3 times).
Retry Interval	The interval, in seconds, between dial-up retries (the default is 10 seconds).