@mrjkenward
This is not always possible.
How to Use Your Router and ISP’s Modem/Router Combo In Tandem
Strange article from 2016, warns you about double NAT and how to resolve it. Then finishes off giving advice on using the DMZ where a modem is not available not warning you will result in double NAT. Maybe it should already be realised by reading the article.
I understand in some situations double NAT can't be avoided, but where possible it should be. So with a plusnet hub two use it as a modem. With the Hub One I had no choice other than using the DMZ
If you're looking to segment your network then a second router would be the way ahead.
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