> In some places it sounds like the ONT is integrated with the router (like with DOCSIS), and being forced to use the ISP’s router is a problem.

I agree, and that is a problem. The rules and regulations are different in different countries. In Austria for instance the ISP can force you to use a specific DOCSIS modem or ONT but they have to provide you with a transparent way to connect to it (bridge mode etc.). Which from where I'm standing is a good tradeoff because it gives the ISP the flexibility to do mass migrations without having to consider very old deployed infrastructure.

With PON I think it doesn't matter all _that_ much but for instance people running ancient DOCSIS modems and limited frequency availability has been a massive pain for people stuck with DOCSIS infrastructure that want more upstream and can't.

> But in cases where the ONT just looks like a media converter and you have a separate router

That's how it works in New Zealand, but we take it a step further. The GPON/XGS-PON fibre network is run by a separate company[0] from the ISPs (and the company running the fibre network is prohibited from providing internet services[1]). So the ONT just functions as a media converter[2], and all our ISPs deliver internet over the same fibre network. This decoupling between the fibre network provider and ISP means you can change ISPs without any swapping of ONTs or repatching of fibre[3][4] (in fact, the process can be entirely automated, switching to some ISPs can take effect within an hour or two of placing the order). That and most ISPs allow bringing your own router (as there's no monopoly in the ISP space).

[0]: The NZ Government contracted four companies to build, own, and run fibre networks (three being new companies co-owned by local lines companies and the government to serving their local area, with the rest of the country being served by Chorus, the company that owns the country's copper network). These fibre companies are heavily regulated (including how much they can charge ISPs).

[1]: In fact, this requirement resulted in Telecom (the company that owned our copper network and who was one of the companies that provided phone and internet service to consumers) being split up, with Chorus being spun off, owning the copper network and owning the fibre network for the majority of the country.

[2]: Chorus did start deploying ONTs with a built-in router/AP a while back. They did offer this to ISPs to use, but uptake was very low, so it's since been discontinued.

[3]: I don't know how it works over in European countries where ISPs run their own fibre networks when switching ISPs, I assume they have to either install their own fibre line into the premises or the existing fibre is repatched to their network?

[4]: The fibre companies are required to offer use of their fibre network directly to ISPs, with the ISPs PON network running in parallel to the fibre company's, with the ISP providing their own fibre splitters and ONTs (which would be run on a second fibre line that each premises already has) and running their own OLTs. I believe this requirement still exists, but no-one ever took them up on it.

In theory the ONT can act like a listening device. They're also often Linux or BSD devices that can get hacked.

If you're paranoid, you may want to run an ONT that you control, just in case. I doubt it's something that matters to a lot of people, but even if it only matters to some, it shouldn't be made impossible for those that want to.

RE: misbehaving hardware: the same is very much true for cable internet and there are plenty of countries where people hook up their own modem without any trouble. If someone wanted to mess with the fiber network they could just disconnect the ONT and shine a laser pointer down there. All off-the-shelf devices are built to just work and follow the necessary standards, because there's nothing to be gained by messing with the PON network like that.

You are at the end of the day still running a business.

It's like saying that Spotify could suddenly decide to retire support for Android 12 or something. They could, but how many customers are they going to lose and how much support burden is that going to generate?

> Why? There is nothing preventing an ISP from saying that from date X, only protocols A, B and C are supported. If you want to use your own device, make sure it supports these protocols.

A lot of overhead for ISP support in those cases in which a customer knows they can buy any router with any ONT, plugs it and forgets it without zero knowledge of what a protocol even is.

Hahahaha! Have you ever done any customer support!? This is not how it works.

Do you know how this works contract wise? When you get network are you guaranteed that GPON will work or can they refuse service after a certain point in time and force you to upgrade to XGS-PON (or some other standard)?

jailtime for a mouthful of internet is somewhat of a stretch

> but at the end of the day it's still running over a shared medium

Everything is eventually a shared medium. You don't have your own fiber all the way to Facebook. So the question is just at which point do you share and that should be a decision made on throughput and cost.

Even if you have AON you might have XGS-PON behind the scenes. In Switzerland end user fiber is AON more or less by regulation, but they just deploy the XGS-PON splitters in the COs.

The low end doesn't have to deal with AON vs GPON. They get DSL or DOCSIS, or if they're unlucky dial-up.

And when the poor souls on slow internet do get upgraded, AON vs GPON suddenly decides if they can get upgraded to the new higher speeds in the next ten years or not. 1gbps may be relatively slow in 10 years, but with a widely spread GPON you're not getting much more out of that, while with AON entire neighbourhoods can be upgraded by replacing a single rack in the local POP.

> poor souls, though can we care about the low-end first?

What is the low end? Austria has a similar problem. There are some quite old and unmaintained AON networks where people are stuck with 100MBit whereas even G.Fast copper eclipses that in some cities at this point.

> It's equivalent to an old POTS party line

I strongly disagree. On a party line information flows along the copper cable to every connected endpoint bidirectionally. While it's true that incoming information flows to all subscribers, never does information that flows out and you only get scrambled data even on the incoming stream. So if you're trying to make a security argument: the system is also safe on a physical level.

> We can do better!

Depends on what "better" is. I was quite critical of PON in the past but I have come around. Practically at this point I think PON is a better way to run networks in most places. At one point you hit a bottleneck anyways and not having to run individual fibers makes for a more resilient and cheaper system.

Yes, exactly like one of those old copper POTS party lines - remember how providers could easily supply a reliable symmetrical multi-gigabit service over those (like we can with XGS-PON) and how they theoretically could use DWDM to move hundreds of gigabits over them? No??

What are the alternatives with passive splitter hardware that can work underwater if shit happens?