HIKVISION DS-9600NI-I8 Series User Manual page 160

Go to Configuration → System → Security → Security Service via web browser to enable/disable
serial port authentication service.
Service Close Time
The serial port authentication service will be closed for a specific period. For example, if Service
Close Time is set as 30, the serial port authentication service will be closed for 30 days. And
after 30 days, serial port authentication service will be enable.
Network Video Recorder User Manual
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