8 ms·

As far as I'm aware, they are only required to allow you to use your own router. DSL tech is far simpler and it's always a combo unit so I could see a case whe

As far as I'm aware, they are only required to allow you to use your own router. DSL tech is far simpler and it's always a combo unit so I could see a case where you would be allowed to bring your own DSL modem. But it just doesn't work like that for DOCSIS or GPON where the cable modems or ONTs these days do much more than just media conversion - SIP, PPPoE, IGMP, etc. even if they don't do Wi-Fi (so ISPs don't call them "routers" - except SingTel, which uses "ONR" to distinguish these units because they are in fact routers for IPTV and SIP). For all of those modems/ONTs, the firmware updates and the configuration for telephony/SIP and PPPoE are controlled by the ISP and also tested to work with their OLT or CMTS so it's just not possible for the ISP to guarantee support for any random modem or ONT. And to support the advanced configuration required these days for VoIP, IPTV, etc. on the "modem" or "ONT", ISPs basically have a backdoor called TR-069 which is really not too dissimilar to what Starlink has access to with their SSH keys. Even if you get "true" dumb modems or ONTs which do not do any routing whatsoever, the device on the other side still has full control over your dumb device via the DOCSIS provisioning process or GPON's OMCI. Starlink seems to be using SSH instead of building a whole protocol - because satellite tech is proprietary and doesn't need to work on other hardware. 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. At most, I think using your own router would require the EU ISPs to provide bridge mode support, but that's not special to EU. However, the TR-069 backdoor is still active even with bridge mode. It can be fairly easy to stop TR-069 with a "dumb" ONT (usually SFP) but ISPs can and will notice that. Whether they allow it is up to them.

bkor 1y ago
> 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/eigen-modem#vragen 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 1y ago
  "Your" modem is netbooting "their" firmware and they have full remote access on a management interface.
  - kotaKat 1y ago
    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.
    - microtonal 1y ago
      I don't know much about DOCSIS, but this is absolutely false for fiber here in The Netherlands. You can hook up your own OPNsense machine (or whatever you like) with an SFP+ module of your own choosing (as long as the transmitter is compatible, etc.). There is no way for the ISP to do any remote management. DOCSIS is slowly dying here anyway and bleeding customers because the cable providers are not competitive when it comes to internet. If they didn't have better linear TV packages the bleed would even be larger.
      - kotaKat 1y ago
        DOCSIS modems require a configuration file from the cable modem termination system. This dictates the whole configuration from RF map and channel plan to things like QoS and management. Even with a customer-supplied modem, the CMTS will still supply a configuration file the modem must obey (and the CMTS will enforce). For many modems on the customer market this also can mean that the ISP can push their own version of the firmware for a modem if you buy identical - such as pushing SURFboard updates.
claudex 1y ago
>DSL tech is far simpler and it's always a combo unit so I could see a case where you would be allowed to bring your own DSL modem. Not really, when you want to increase the bandwith, e.g. with vectoring[1], you need to have all neighbor modems to participate, which prevent free modem choice for the users. >But it just doesn't work like that for DOCSIS or GPON where the cable modems or "ONT" router combo units these days do much more than just media conversion - SIP, PPPoE, IGMP, etc. In Belgium, the ONT is just media conversion these days, SIP is done on the provider box, so you can have your own GPON SFP. >so it's just not possible for the ISP to guarantee support for any random modem or ONT. The ISP doesn't have to guarantee support to let you use your own hardware. It just have to give you the specs to use it and let you plug the ISP box if you can't configure vlan of dhcpv6 client. [1]: https://en.wikipedia.org/wiki/VDSL#VDSL2_vectoring https://en.wikipedia.org/wiki/VDSL#VDSL2_vectoring
- claudex 1y ago
  Each country regulator in the European Union have to set it's own regulation, but the BEREC (Association of UE telecom regulators) guidelines say that in most case, the free choice of router and modem is what's is required by the EU decisions https://www.berec.europa.eu/sites/default/files/files/document_register_store/2020/3/BoR_(20)_46_BEREC_Guidelines_NTP.pdf https://www.berec.europa.eu/sites/default/files/files/docume...
fx1994 1y ago
Provider will not support my modem that is for sure so if you have any issues you are on your own. I use my own Mikrotik + Zyxel PMG3000 GPON SPF and no issues at all.
chgs 1y ago
Not the case in the U.K., dal or fibre doesn’t matter, domestically you typically have a standard sfp or other converter from anywhere which presents it as Ethernet which you then run pppoe over. Tr069 allows the isp to remotely configure their equipment which most people are happy with, but if you want to use your own then that’s fine, and obviously unless you enable it the isp won’t configure your router or any other equipment. Starlink acts far more than a media converter.
AnssiH 1y ago
> But it just doesn't work like that for DOCSIS or GPON where the cable modems or ONTs these days do much more than just media conversion - SIP, PPPoE, IGMP, etc. even if they don't do Wi-Fi (so ISPs don't call them "routers" - except SingTel, which uses "ONR" to distinguish these units because they are in fact routers for IPTV and SIP). At least in Finland the norm is that you can use your own DOCSIS modem from any manufacturer, you just tell the ISP your modem's MAC address. Not for GPON, though.
- devmor 1y ago
  Same here in the US. You can bring your own DOCSIS modem to any cable internet provider.
  - bombela 1y ago
    For me, Comcast only allowed a few models. Because it requires full control. They uploaded a Comcast firmware on it. And they warned me that after that the device is basically stuck to only work with Comcast. This was around 2017.
    - devmor 1y ago
      That sounds odd - I wonder if it was a relic of your local infrastructure. I used my own DOCSIS modem with its own firmware on Comcast around the same time. It was a generic Arris Surfboard.
      - genocidicbunny 1y ago
        Comcast's list of approved devices includes (or used to at least) some of the more common Arris Surfboards; I also used one when I had Comcast service. You probably also used one that was 'compatible'.
        devmor 1y ago
        The list of compatible devices was simply a list of all devices that supported DOCSIS 3.1 at the time. At no point was my firmware swapped out, or anything of that nature.
fucker42069 1y ago
[dead]
connicpu 1y ago
On Xfinity you can BYO DOCSIS modem. It has to be from an approved list of manufacturers, but I purchased my own DOCSIS modem back when you had to do that in order to receive gigabit internet service (it was still early days of the rollout).
immibis 1y ago
Modems are part of the ISP's network. Where does the ISP's network end, and your network begin? You might be tempted to say it's at the wall jack, but your ISP is tempted to say it doesn't, and your computer is theirs too. In the past (and again on some fiber networks), there was https://en.wikipedia.org/wiki/Network_interface_device https://en.wikipedia.org/wiki/Network_interface_device and the separation occurred there. Note that it might not be the same at L1 and L2, e.g. your ISP may own the physical lines up to the side of your building, and the data link layer up to your modem.
Tijdreiziger 1y ago
They do have to allow own modems as well as routers. Article 5 of the EU Net Neutrality Regulation states that “end-users should be free to choose between various types of terminal equipment […]. Providers of internet access services should not impose restrictions on the use of terminal equipment connecting to the network […].” [1] However, currently only 5 member states fully comply with this (Germany, the Netherlands, Belgium, Finland and Lithuania). [2] E.g. NL ISPs provide all necessary parameters for PPPoE and SIP (telephony). [3] [1] https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:OJ.L_.2015.310.01.0001.01.ENG https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:... [2] https://fsfe.org/activities/routers/routers.en.html https://fsfe.org/activities/routers/routers.en.html [3] https://www.kpn.com/w3/file?uuid=cd5f3398-4bad-4cdc-ac18-4f63361931b5&owner=8de86c61-bdc8-4848-872e-e5b380e682fc&contentid=50186 https://www.kpn.com/w3/file?uuid=cd5f3398-4bad-4cdc-ac18-4f6... (DSL) https://www.kpn.com/w3/file?uuid=563993a1-e48a-485a-90a8-7389c5d6f5d4&owner=8de86c61-bdc8-4848-872e-e5b380e682fc&contentid=50183 https://www.kpn.com/w3/file?uuid=563993a1-e48a-485a-90a8-738... (FttH AON/PON) https://www.kpn.com/w3/file?uuid=b9774a1d-f1cb-4c17-8972-2512455bde2d&owner=8de86c61-bdc8-4848-872e-e5b380e682fc&contentid=50184 https://www.kpn.com/w3/file?uuid=b9774a1d-f1cb-4c17-8972-251... (SIP)
- raron 1y ago
  I don't think that is true for modems, there is an "exception" for indirectly connected terminal equipments. Interestingly satellite earth station is explicitly mentioned, so maybe we can use our own Starlink dish, but not out own modem... (law is weird) ‘terminal equipment’ means: (a) equipment directly or indirectly connected to the interface of a public telecommunications network to send, process or receive information; in either case (direct or indirect), the connection may be made by wire, optical fibre or electromagnetically; a connection is indirect if equipment is placed between the terminal and the interface of the network; (b) satellite earth station equipment; https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv%3AOJ.L_.2008.162.01.0020.01.ENG&toc=OJ%3AL%3A2008%3A162%3ATOC https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv%...
  - Tijdreiziger 1y ago
    I’m not a lawyer, so perhaps I’m missing something, but I don’t see any exception in your quote or link. Your quote literally says ”equipment directly or indirectly connected” (emphasis mine). The Netherlands regulator interprets this by saying that “the network connection point must be passive” and “all (radio) devices that are located at the premises of the end user and that are connected to the network connection point are end devices”. [1] [1] https://www.acm.nl/system/files/documents/beleidsregel-handhaving-besluit-eindapparaten.pdf https://www.acm.nl/system/files/documents/beleidsregel-handh... (Dutch)
microtonal 1y ago
As far as I'm aware, they are only required to allow you to use your own router. No. At least in The Netherlands the regulations are very clear. Any device that directly or indirectly connected to fiber, copper, or 'electromagnetic waves': https://wetten.overheid.nl/BWBR0038908/2016-12-28/#Artikel1 https://wetten.overheid.nl/BWBR0038908/2016-12-28/#Artikel1 Also, if you read the rest of the regulation, they make it very clear that the ISP should accommodate the user making it possible to use a passive end from the ISP (so, just the fiber/copper, with no active devices from the ISP required): https://wetten.overheid.nl/BWBR0045477/2022-01-27 https://wetten.overheid.nl/BWBR0045477/2022-01-27 ONTs these days do much more than just media conversion - SIP, PPPoE, IGMP The ONT (at least in the definition used in our country) only does media conversion. Usually a dedicated device is used as the ONT (Genexis/Nokia ONT) that just does the fiber <-> ethernet media conversion. You can use the ISP's or bring your own. Some people use an SFP+ module as the ONT. PPPoE, SIP, etc. are usually handled by a combined router/modem. For all of those modems/ONTs, the firmware updates and the configuration for telephony/SIP and PPPoE are controlled by the ISP and also tested to work with their OLT or CMTS so it's just not possible for the ISP to guarantee support for any random modem or ONT. It is not a problem in practice. E.g. my provider allows you to bring your modem/router, as long as it supports PPPoE and VLANs. For example, I currently use the provider's media converter and use a Unifi Gateway Max as my modem/router (it does PPPoE). Before that I had fiber directly hooked up to my own Fritz!Box with an SFP+ module. I'm on some Dutch tech forums and people use a lot of different equipment: - ONT: provider or their own media converter, or an SFP+ module (typically Zaram or AVM). - Router/modem: Unifi (e.g. Cloud Gateway with fiber <-> ethernet converter or a Dream Machine with an SFP+ module), OPNsense (handles PPPoE as well), Fritz!Box, a plain old Linux distribution, OpenWrt (seems more rare). ONTs which do not do any routing whatsoever, the device on the other side still has full control over your dumb device via the DOCSIS provisioning process or GPON's OMCI I think ONTs are less of a problem, because it's on the other side of a security boundary. The modem/gateway is where you don't want an ISP backdoor. 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. It is, as long as the ONT and modem correspond to the specs. E.g. my provider requires PPPoE and VLANs [1]. As long a router/modem supports it, they have to allow it. Of course, they don't have to debug issues inside, say a Unifi gateway for you. But if such a device fulfills the requirements, they have to allow it on their network. Again, people here do all kinds of stuff. Like recently I saw someone who uses a Banana PI R4 with a Zaram SFP+ module as their ONT+modem/router. And the ISP has to allow it, because the user is allowed to replace any active component. When I experimented a bit with SFP+ modules, etc., I had the ISP on the phone some times and they were very helpful and accommodating and said that my setup was pretty normal compared to what they saw some other tech people doing. [1] https://assets.ctfassets.net/zuadwp3l2xby/2Yp0HtLJPKBUX5mqr3l23a/936f91d56ff916c1f8f5c81d195bcd4f/20222263_KPN_Internet_Glasvezel_Specificaties_v20230123.pdf https://assets.ctfassets.net/zuadwp3l2xby/2Yp0HtLJPKBUX5mqr3...

bkor 1y ago

> 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/eigen-modem#vragen 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 1y ago
"Your" modem is netbooting "their" firmware and they have full remote access on a management interface.
- kotaKat 1y ago
  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.
  - microtonal 1y ago
    I don't know much about DOCSIS, but this is absolutely false for fiber here in The Netherlands. You can hook up your own OPNsense machine (or whatever you like) with an SFP+ module of your own choosing (as long as the transmitter is compatible, etc.). There is no way for the ISP to do any remote management. DOCSIS is slowly dying here anyway and bleeding customers because the cable providers are not competitive when it comes to internet. If they didn't have better linear TV packages the bleed would even be larger.
    - kotaKat 1y ago
      DOCSIS modems require a configuration file from the cable modem termination system. This dictates the whole configuration from RF map and channel plan to things like QoS and management. Even with a customer-supplied modem, the CMTS will still supply a configuration file the modem must obey (and the CMTS will enforce). For many modems on the customer market this also can mean that the ISP can push their own version of the firmware for a modem if you buy identical - such as pushing SURFboard updates.

claudex 1y ago

>DSL tech is far simpler and it's always a combo unit so I could see a case where you would be allowed to bring your own DSL modem. Not really, when you want to increase the bandwith, e.g. with vectoring[1], you need to have all neighbor modems to participate, which prevent free modem choice for the users. >But it just doesn't work like that for DOCSIS or GPON where the cable modems or "ONT" router combo units these days do much more than just media conversion - SIP, PPPoE, IGMP, etc. In Belgium, the ONT is just media conversion these days, SIP is done on the provider box, so you can have your own GPON SFP. >so it's just not possible for the ISP to guarantee support for any random modem or ONT. The ISP doesn't have to guarantee support to let you use your own hardware. It just have to give you the specs to use it and let you plug the ISP box if you can't configure vlan of dhcpv6 client. [1]: https://en.wikipedia.org/wiki/VDSL#VDSL2_vectoring https://en.wikipedia.org/wiki/VDSL#VDSL2_vectoring

claudex 1y ago
Each country regulator in the European Union have to set it's own regulation, but the BEREC (Association of UE telecom regulators) guidelines say that in most case, the free choice of router and modem is what's is required by the EU decisions https://www.berec.europa.eu/sites/default/files/files/document_register_store/2020/3/BoR_(20)_46_BEREC_Guidelines_NTP.pdf https://www.berec.europa.eu/sites/default/files/files/docume...

fx1994 1y ago

Provider will not support my modem that is for sure so if you have any issues you are on your own. I use my own Mikrotik + Zyxel PMG3000 GPON SPF and no issues at all.

chgs 1y ago

Not the case in the U.K., dal or fibre doesn’t matter, domestically you typically have a standard sfp or other converter from anywhere which presents it as Ethernet which you then run pppoe over. Tr069 allows the isp to remotely configure their equipment which most people are happy with, but if you want to use your own then that’s fine, and obviously unless you enable it the isp won’t configure your router or any other equipment. Starlink acts far more than a media converter.

AnssiH 1y ago

> But it just doesn't work like that for DOCSIS or GPON where the cable modems or ONTs these days do much more than just media conversion - SIP, PPPoE, IGMP, etc. even if they don't do Wi-Fi (so ISPs don't call them "routers" - except SingTel, which uses "ONR" to distinguish these units because they are in fact routers for IPTV and SIP). At least in Finland the norm is that you can use your own DOCSIS modem from any manufacturer, you just tell the ISP your modem's MAC address. Not for GPON, though.

devmor 1y ago
Same here in the US. You can bring your own DOCSIS modem to any cable internet provider.
- bombela 1y ago
  For me, Comcast only allowed a few models. Because it requires full control. They uploaded a Comcast firmware on it. And they warned me that after that the device is basically stuck to only work with Comcast. This was around 2017.
  - devmor 1y ago
    That sounds odd - I wonder if it was a relic of your local infrastructure. I used my own DOCSIS modem with its own firmware on Comcast around the same time. It was a generic Arris Surfboard.
    - genocidicbunny 1y ago
      Comcast's list of approved devices includes (or used to at least) some of the more common Arris Surfboards; I also used one when I had Comcast service. You probably also used one that was 'compatible'.
      - devmor 1y ago
        The list of compatible devices was simply a list of all devices that supported DOCSIS 3.1 at the time. At no point was my firmware swapped out, or anything of that nature.

fucker42069 1y ago

[dead]

connicpu 1y ago

On Xfinity you can BYO DOCSIS modem. It has to be from an approved list of manufacturers, but I purchased my own DOCSIS modem back when you had to do that in order to receive gigabit internet service (it was still early days of the rollout).

immibis 1y ago

Modems are part of the ISP's network. Where does the ISP's network end, and your network begin? You might be tempted to say it's at the wall jack, but your ISP is tempted to say it doesn't, and your computer is theirs too. In the past (and again on some fiber networks), there was https://en.wikipedia.org/wiki/Network_interface_device https://en.wikipedia.org/wiki/Network_interface_device and the separation occurred there. Note that it might not be the same at L1 and L2, e.g. your ISP may own the physical lines up to the side of your building, and the data link layer up to your modem.

Tijdreiziger 1y ago

They do have to allow own modems as well as routers. Article 5 of the EU Net Neutrality Regulation states that “end-users should be free to choose between various types of terminal equipment […]. Providers of internet access services should not impose restrictions on the use of terminal equipment connecting to the network […].” [1] However, currently only 5 member states fully comply with this (Germany, the Netherlands, Belgium, Finland and Lithuania). [2] E.g. NL ISPs provide all necessary parameters for PPPoE and SIP (telephony). [3] [1] https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:OJ.L_.2015.310.01.0001.01.ENG https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:... [2] https://fsfe.org/activities/routers/routers.en.html https://fsfe.org/activities/routers/routers.en.html [3] https://www.kpn.com/w3/file?uuid=cd5f3398-4bad-4cdc-ac18-4f63361931b5&owner=8de86c61-bdc8-4848-872e-e5b380e682fc&contentid=50186 https://www.kpn.com/w3/file?uuid=cd5f3398-4bad-4cdc-ac18-4f6... (DSL) https://www.kpn.com/w3/file?uuid=563993a1-e48a-485a-90a8-7389c5d6f5d4&owner=8de86c61-bdc8-4848-872e-e5b380e682fc&contentid=50183 https://www.kpn.com/w3/file?uuid=563993a1-e48a-485a-90a8-738... (FttH AON/PON) https://www.kpn.com/w3/file?uuid=b9774a1d-f1cb-4c17-8972-2512455bde2d&owner=8de86c61-bdc8-4848-872e-e5b380e682fc&contentid=50184 https://www.kpn.com/w3/file?uuid=b9774a1d-f1cb-4c17-8972-251... (SIP)

raron 1y ago
I don't think that is true for modems, there is an "exception" for indirectly connected terminal equipments. Interestingly satellite earth station is explicitly mentioned, so maybe we can use our own Starlink dish, but not out own modem... (law is weird) ‘terminal equipment’ means: (a) equipment directly or indirectly connected to the interface of a public telecommunications network to send, process or receive information; in either case (direct or indirect), the connection may be made by wire, optical fibre or electromagnetically; a connection is indirect if equipment is placed between the terminal and the interface of the network; (b) satellite earth station equipment; https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv%3AOJ.L_.2008.162.01.0020.01.ENG&toc=OJ%3AL%3A2008%3A162%3ATOC https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv%...
- Tijdreiziger 1y ago
  I’m not a lawyer, so perhaps I’m missing something, but I don’t see any exception in your quote or link. Your quote literally says ”equipment directly or indirectly connected” (emphasis mine). The Netherlands regulator interprets this by saying that “the network connection point must be passive” and “all (radio) devices that are located at the premises of the end user and that are connected to the network connection point are end devices”. [1] [1] https://www.acm.nl/system/files/documents/beleidsregel-handhaving-besluit-eindapparaten.pdf https://www.acm.nl/system/files/documents/beleidsregel-handh... (Dutch)

microtonal 1y ago

As far as I'm aware, they are only required to allow you to use your own router. No. At least in The Netherlands the regulations are very clear. Any device that directly or indirectly connected to fiber, copper, or 'electromagnetic waves': https://wetten.overheid.nl/BWBR0038908/2016-12-28/#Artikel1 https://wetten.overheid.nl/BWBR0038908/2016-12-28/#Artikel1 Also, if you read the rest of the regulation, they make it very clear that the ISP should accommodate the user making it possible to use a passive end from the ISP (so, just the fiber/copper, with no active devices from the ISP required): https://wetten.overheid.nl/BWBR0045477/2022-01-27 https://wetten.overheid.nl/BWBR0045477/2022-01-27 ONTs these days do much more than just media conversion - SIP, PPPoE, IGMP The ONT (at least in the definition used in our country) only does media conversion. Usually a dedicated device is used as the ONT (Genexis/Nokia ONT) that just does the fiber <-> ethernet media conversion. You can use the ISP's or bring your own. Some people use an SFP+ module as the ONT. PPPoE, SIP, etc. are usually handled by a combined router/modem. For all of those modems/ONTs, the firmware updates and the configuration for telephony/SIP and PPPoE are controlled by the ISP and also tested to work with their OLT or CMTS so it's just not possible for the ISP to guarantee support for any random modem or ONT. It is not a problem in practice. E.g. my provider allows you to bring your modem/router, as long as it supports PPPoE and VLANs. For example, I currently use the provider's media converter and use a Unifi Gateway Max as my modem/router (it does PPPoE). Before that I had fiber directly hooked up to my own Fritz!Box with an SFP+ module. I'm on some Dutch tech forums and people use a lot of different equipment: - ONT: provider or their own media converter, or an SFP+ module (typically Zaram or AVM). - Router/modem: Unifi (e.g. Cloud Gateway with fiber <-> ethernet converter or a Dream Machine with an SFP+ module), OPNsense (handles PPPoE as well), Fritz!Box, a plain old Linux distribution, OpenWrt (seems more rare). ONTs which do not do any routing whatsoever, the device on the other side still has full control over your dumb device via the DOCSIS provisioning process or GPON's OMCI I think ONTs are less of a problem, because it's on the other side of a security boundary. The modem/gateway is where you don't want an ISP backdoor. 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. It is, as long as the ONT and modem correspond to the specs. E.g. my provider requires PPPoE and VLANs [1]. As long a router/modem supports it, they have to allow it. Of course, they don't have to debug issues inside, say a Unifi gateway for you. But if such a device fulfills the requirements, they have to allow it on their network. Again, people here do all kinds of stuff. Like recently I saw someone who uses a Banana PI R4 with a Zaram SFP+ module as their ONT+modem/router. And the ISP has to allow it, because the user is allowed to replace any active component. When I experimented a bit with SFP+ modules, etc., I had the ISP on the phone some times and they were very helpful and accommodating and said that my setup was pretty normal compared to what they saw some other tech people doing. [1] https://assets.ctfassets.net/zuadwp3l2xby/2Yp0HtLJPKBUX5mqr3l23a/936f91d56ff916c1f8f5c81d195bcd4f/20222263_KPN_Internet_Glasvezel_Specificaties_v20230123.pdf https://assets.ctfassets.net/zuadwp3l2xby/2Yp0HtLJPKBUX5mqr3...