Thanks for answering me again, I am still struggling to understand however. Probably me and not you.
I believe that the External RADIUS part of the General tab in the Services | Hotspot configuration pages allows me to configure an external radius server which can be used to control clients access to the Hotspot Wifi and what those clients will be able to do. I think that is NOT the same as logging on to the web configuration pages for the RUT240. The password for logging in to the RUT240 is configured in the System | Administration page under the General tab. In fact, in my case WiFi is disabled and so no hotspot should be possible anyway.
Authentication on to the Hotspot allows a client access to the network, but to access the RUT240 pages they would still have to log on to the configuration pages using a separate authentication mechanism, the password for which is set in the System | Administration page under the General tab. Were I to enable external RADIUS authentication for the Hotspot pointing at an appropriate external server and then disable all WiFi I imagine that this RADIUS authentication mechanism would never be used.
It seems unlikely that the external RADIUS server settings for authentication on to the RUT240's configuration pages would be hidden within the Hotspot settings? Rather it would be in the System Administration pages if indeed it were possible. This is what leads me to believe that authentication into the RUT240 web configuration pages is not possible from an external RADIUS server.
Have I misunderstood any of the above, or got it wrong or made incorrect assumptions? Is so, please can you correct my misunderstanding?
Many thanks for putting up with the questioning and any help you can give.