Inbound Channel Testing

The Channel Manager sends a periodic ‘AT’ command to inbound and inbound/outbound modems. This test allows the Channel Manager to detect a modem, which is no longer connected, for example when the associated terminal server port is unreachable, when the modem is not connected or is unresponsive to commands.

The test is sent periodically (the interval is configurable through the config file entry sendAliveCommandInterval).

When a test fails, the Channel Manager attempts to reset the modem for dial-in detection. Repeated failures result in repeated reset attempts.

All failures result in a suitable error code/string being recorded for the modem device and the error count incremented.