Before BioStar 2.6, some devices couldn't restore to default value without changing network setting.
If you perform Factory Default while using static IP instead of DHCP, you must reconfigure network for the device. However. not all sites have someone who can manage the devices. In this case, the installer must visit the site directly.
To resolve such inconvenience, BioStar 2.6 and above versions provide an option 'Without network' for every device.
With this option, you can reset your device to Factory Default status without changing its network settings.