BTW: in the EU there is movement towards mandating ISPs allow BYOD, including fibre ONTs.

https://fsfe.org/activities/routers/

This can be a good stopgap, but the solution is to lobby for a law that mandates free ONT/modem/router choice.

We have such legislation in NL and the ISP is required to make it possible to use your own equipment.

Coincidentally, I had my ISP register my Fritz!Box Fiber 5590 as my ONT yesterday, so I have it directly hooked up to XGS-PON with their SFP+ module (no more Genexis ONT \o/).

I am so glad that here in Switzerland the government went after the large ISP that tried to install only P2MP instead of the decided on standard of P2P for fiber.

https://blog.init7.net/en/die-glasfaserstreit-geschichte/

Funny, I just got my own GPON-capable SFP (a Zyxel pmg3000-d20b) last week.

Finally got a fiber connection from Deutsche Telekom 2 months ago, after almost 5 years of waiting and a huge amount of fear and loathing. At one point, they threatened to cancel my order, claiming a certain subcontractor was unable to reach me. Of course that subcontractor had already done it's job months ago at that point. And this is just one of the many, many shenanigans that went on during those years.

At the moment, I'm using a Fritz!Box 5530 Fiber directly hooked up to the fiber with the AVM-supplied GPON interface. But I'm planning for the Zyxel SFP to go directly into my homelab server and route from there :)

It is my understanding that ISPs have management software that watches all the ONT activities. They will mark a rogue ONT as an “alien” and blacklist it.

Where I live, you can replace an ONT easily. GPON in my small country is only secured with the ONT serial number and a static well known password.

From a security perspective, that's perfectly fine. No one is going to hack their own neighbours or dig out fibre cables. From a usability and freedom of hardware choice, that's even better -- SN is written on the ONT and can be easily input into another ONT, unlike passwords and encryption keys that are largely unnecessary and only complicate things, providing little security because no one will hack GPON infrastructure.

You run into problems, however, if you are subscribed to telephony. It's possible that the ONT will handle VoIP for you and provide you just with a RJ11 jack. In that case, you can't easily swap your ONT. But for IPTV and Internet, it works out of the box.

I’m a bell customer in Canada and it used to be the case that the ISP provided modem had a CPU too slow to run PPPoE at a gigabit despite the ISP selling plans up to 1.5gb/s (it could only do 600mb/s or something but don’t quote me). That model has a sfp ont and so you could swap it into something else with no hacking but now you can only get the model with the ont built it. The new model is better hardware wise but just as bad software wise so it feels like a step back in practice.

I think selling users SFP ONTs is probably the right balance of ISP control vs allowing customer freedom

I can only pray this births a ddwrt equivalent for fiber ONTs.

I’m caretaking for my parents who are on ATT fiber with their giant scary black box ONT, and am consistently paranoid of what it is attempting or is doing on their network. This would be a great way to gain more transparency in its operation and possibly open useful features.

My ISP called me a while back and told me that they're decommissioning all copper infra, so it'd be better if I switch to fiber. I said OK.

They brought in a Nokia GPON ONT, and a new Zyxel router. I protested against the router, and I was ready to bypass it with bridge mode (whiich it allows), but with a reliable, powerful, and flexible WiFi6 router with better coverage than my WiFi5 one won over me, and I left it in service.

The thing is a beast with 4 different SSIDs plus a guest network, full gigabit ports and reliable operation. Plus it terminates my POTS line, too. It can handle the full 1000/50 mbps network without even getting warm, either.

So all in all, it's not a bad device overall, and I'm a happy camper.

I have an XGS-PON ONT at home (an Adtran SDX 622v) to support the symmetric 8Gbps connection I have, but it's so basic that I can't really see what benefit there would be to replacing it or hacking it.

It just works, and I can plug my own router in to it.

Being forced to used an ISPs fiber router can be frustrating, I hope we can get regulations to force BYO

I just want to say thank you! This is truly great work and could be an inflection point for fiber optic ISP consumers. Many people have been quietly seeking this solution for years, without finding a response. For those unfamiliar with what this means, take a moment to understand that many of these acronyms and technologies have been part of your fiber optic connection without you even realizing it.

I’d also like to mention that the ‘workaround’ for many was to use the pass-through option in their routers, but not all ISP-provided routers offered that feature!

The fat warning about optics make me realize a fibre optic cable can transmit light straight to the ISP's box (or can it?), and that it might be possible to shoot a laser to do some damage at the other end of a communication link, however little.

That makes me think of this Danger 5 scene: https://www.youtube.com/watch?v=rDhrjKZprOo

I wonder how ISPs would react to this. They're usually not thrilled about customers messing with their gear.

GPON is one of those technologies that should have been drowned in the bath before the spec even made it out of its ITU committee. It's just yet another patch papering over how cheap the ISPs were and how they continue to be. Yes, let's add another layer on top of all of the other layers. Now however many millions of links out to subscribers are hamstrung with that decision to split the physical layer up and throw in nonsensical TDM into the mix as well. Good luck squeezing much out beyond 25g in the future, you're just gonna have to rip all of that fiber up anyway and do home runs. Might as well have done it up front with all of the billions that have been given away to the littly piggy piggy ISPs.

I made a comment a few days ago about how I despair when I see anything modern datacenter related. I get the same sort of revulsion when I look at the list of all of the gpon hardware on that page and thing: how much duplicated and wasted effort has gone in to making dozens of different models of the exact same thing. A thing that's not really even needed if a halfway-competent ISP made an investment that's more than the absolute minimum required.

Nice directory democratizing some good reverse engineering, though!

</end soapbox>

GPON has been such a bad idea...

One fiber, One ISP port has always been the right way.

a bit more practical guides for those who want to swap ONT to SFP https://pon.wiki/

It's an interesting site but where's the 0xbeef? OK it explains how to telnet into some units but then what? How do I get the free HBO ser?

The future needs at least one completely Open Source, Open Hardware ONT... ideally several...

A Google search at this point in time seems to fail to locate even one...

The next best thing (a step in that direction) might be open source firmware for existing proprietary ONT's, for which I found the following links for people who are apparently attempting getting something like that working:

"Has anyone tried making custom firmware for your ONT?":

https://broadband.forum/threads/has-anyone-tried-making-cust...

"Build for Nokia G-2425G-A":

https://forum.openwrt.org/t/build-for-nokia-g-2425g-a/106936

Anyway, the future needs a completely Open Source, Open Hardware ONT...

All I want is to replace the accursed ISP's integrated GPON+router box.

Visited site, and tried to find SFP+ GPON modules that can do 2.5gbps.

It doesn't seem to have a simple list of SFP modules at all. Wtf?

GPON = Gigabit Passive Optical Network ONT = Optical Network Terminal OLT = Optical Line Termination SFP = Small Form-factor Pluggable