[bkor]

> So, I find that it's highly unlikely that the ISP is officially required to support a user supplied modem, although I haven't consulted the EU laws on this.

Ziggo (called UPC in other EU countries) uses DOCSIS. The instructions on how to use your own DOCSIS modem are at the following link (in Dutch): https://www.ziggo.nl/klantenservice/apparaten/wifi-modems/ei...

Edit: it really is using your own modem. It's not about putting it in bridge mode.

[donnachangstein]

"Your" modem is netbooting "their" firmware and they have full remote access on a management interface.

[kotaKat]

This. I can just provision in the backdoor interface on the modem with a config file anyways and gain access.

Plus depending on model (like Arris modems), I can do things like set the password of the day seed (away from the factory default) to further lock it down and gain management access remotely.