• Nfamwap@lemmy.world
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    21 days ago

    This is for PON technology. 1 fibre can be split 32-ways to feed, you guessed it, 32 customers. 50g over a fibre that is split 32-ways with a minimum of 15db loss is impressive.

    I guarantee those 100gbps circuits are a single fibre all the way from the provider to the customer. And they are expensive, very expensive.

    • Kazumara@discuss.tchncs.de
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      20 days ago

      I wonder if they use semiconductor optical amplifiers in the receivers, or if they can make do with avalanche photodiodes.

      The 100G stuff I’m looking at has 18.5 dB budget with APDs, that seems rough considering you want a few kilometers of fiber, a few splices and a few connectors (probably LC/APC) as well.

      • Nfamwap@lemmy.world
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        20 days ago

        I work on PON and XGPON. Officially we work on a -25dB maximum, but I’ve seen circuits stable at around 30dB.

        It’s surprising how many bad splices you can ignore before it gets problematic.

        -18.5dB is going to limit you to either a really good fibre path, or a really short one. Unless you have options with long-range SFPs? The constant progress keeps my job interesting at least.