WPA2 Enterprise RADIUS question


Firmware 7.1.1 on a Surf SOHO.

When using WPA2 Enterprise for an SSID, the web UI has a NAS-Identifier field that is not documented in the Firmware v7 manual from Jan. 2017 (which seems to be the latest edition of the manual). What is it?

As shown in this image, the possible values are LAN MAC Address, Device Serial Number and Custom Value. My experience has been that the option for LAN MAC Address worked fine with the RADIUS server in my LAN-resident Synology NAS box.


Interestingly, this field does not appear when configuring the router to use RADIUS to validate userids for the router itself (System tab -> Authentication by RADIUS checkbox)