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MarkusWandel 3 hours ago

The "glass fiber modem" is an inherent part of the GPON network. These are complicated. The "P" stands for "passive". Yours and and up to 127 other houses are all on the same "light domain" i.e. the downstream is passively split, and the upstream is passively combined, in optical boxes that don't even have electrical parts.

This needs crazy accurate timing for the upstream. The head end needs to know the exact delay to your particular box to give it a "grant" to transmit at exactly the right time so transmit bandwidth is not wasted by idle time or multiple boxes transmitting at the same time and corrupting each other.

You don't want brand X modems with dodgy configurations in this. Of course as a consumer you'd want "as little modem as possible" i.e. just give me an ethernet port running DHCP or PPPOE and let me do the rest.

stephen_g 3 hours ago | parent | next [-]

They are complicated, but standardised and commoditised. Ubiquiti, for example, sells an ONT (fibre modem) in a SFP form factor for US$39 [1], or a little standalone unit with an Ethernet port for US$49 [2].

1. https://store.ui.com/us/en/category/fiber-gpon/products/uf-i...

2. https://store.ui.com/us/en/category/fiber-gpon/products/wave...

direwolf20 3 hours ago | parent [-]

For comparison: you can bring your own DOCSIS modem to a cable network, even though all the houses on the street are connected to the same cable and you could jam it, or send a voltage spike to break everyone's modem.

perching_aix 2 hours ago | parent [-]

Not very familiar with DOCSIS and cable; the story I'm getting from my nearest friendly LLM is that while you could bring your cable modem, it'd have to be a pre-approved model, and that the firmware and configuration would be under ISP control, unlike with DSL modems. Is that wrong?

bobmcnamara 34 minutes ago | parent | prev [-]

I cloned mine into an SFP+ for a handful of microseconds of latency improvement.