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Comment by tristor

7 hours ago

PPPoE is pretty much only used for DSL in the US. I'm not sure about elsewhere.

Xfinity and AT&T Fiber do /not/ use PPPoE. Xfinity is built on DOCSIS, and AT&T Fiber is built on XGSPON. This means neither one relies on PPPoE at the data link layer. XGSPON uses XGEM/XGTC at data link layer, DOCSIS uses MAC (same data link protocol as Ethernet).

This article is making a bunch of assertions which are just patently false. PPPoE is basically old hat at this point. It's extremely high overhead anyway, so is only used for DSL because DSL is an old approach.

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tristor

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microtonal  5 hours ago

It's extremely high overhead anyway, so is only used for DSL because DSL is an old approach.

I have 4Gbit symmetric fiber over PPPoE (+ a VLAN) in NL. It's quite common here in Europe. The Unifi Cloud Gateway Fiber, handles it well though (as mentioned in the article).

dlgeek  6 hours ago

Some of AT&T's fiber acquisitions still use PPPoE including CenturyLink and Quantum's fiber offerings (acquired from Lumen).

  • tristor  6 hours ago

    Quantum Fiber doesn't use PPPoE, it uses IPoE w/ VLAN tagging using VLAN 201, which is a common approach for legacy GPON networks. CenturyLink Fiber does use PPPoE, but I believe only the authentication portion of PPPoE, but I have never had CenturyLink Fiber so I can't say for certain.

    • dlgeek  6 hours ago

      You're right about Quantum. I just went and checked my router config. (I switched from CL to Q about 6 months ago).

      CenturyLink did use a full PPPoE stack though.

    • montjoy  6 hours ago

      I have Quantum and a UCG fiber. IIRC you only have to turn off vlan tagging on the ONT, and then set DHCP and the vlan tag on the UCG. If you try to keep the vlan tag on ONT you will get horrendous latency. The ISP still shows as CenturyLink.

    • toast0  6 hours ago

      I don't know how 'only authentication' from PPPoE would work... If you do PPPoE auth, then you can DHCP? That would be a pretty weird config to setup.

      I know some CenturyLink fiber defaults to PPPoE, but you can ask for IPoE instead.

IneffablePigeon  6 hours ago

Mind telling us which assertions are false? They make no claims about pppoe adoption other than that’s what their connection uses.

My fibre connection in the uk uses pppoe (2gbps)

  • tristor  6 hours ago

    I'm mostly replying to this line "Even in 2026, a huge number of ISPs still rely on PPPoE, including Bell Canada, AT&T Fiber, and Xfinity in the US, along with the vast majority of ISPs in Europe, Asia, and China."