With the speeds increasing, we've forgot about some technologies like ADSL and coax for broadband internet access.
Nowdays, it's more and more likely that you would get fast network speeds to your home with some newer stuff like FTTH (Fiber To The Home) or PON (Passive Optical Network).
With PON, access to the provider's network is achieved through a device called ONT (Optical Network Terminal). This, in most cases is equipment provided by your ISP and it is their property.
Some ISPs may give you permissions to access this equipment, but most of them won't! They will do anything not to give you access and make it harder if not impossible for you to change some options like Wi-Fi SSID or Wi-Fi password.
For some of us, it's important to have full control over the equipment that sits in our house. For others, physical space or energy consumption is the key.
Solution to this problem consists of gathering some data from provider's equipment, then transferring it to another device without begging your ISP for help. In most cases, you will need at least business-grade equipment, like for example Mikrotik.
For now, only solution I have developed is for A1 Bulgaria GPON Service.
This guide is provided as-is without warranty of any kind. Every action on foreign equipment is at your own risk!
I'm creating this repo with hope that anyone who knows something more will contribute.
Feel free to do so!