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46 points PaulHoule | 1 comments | 27 Aug 25 16:28 UTC | HN request time: 0.203s | source

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RantyDave ◴[30 Aug 25 22:52 UTC] No.45078687[source]▶

Sorry, waveguide? For light? I thought that’s what fibre was.

bc569a80a344f9c ◴[30 Aug 25 23:05 UTC] No.45078788[source]▶

It is. But it’s not the only possible waveguide. The article discusses alternatives for a system that can transmit 5-10k signals in 32U. If you’re using fiber optic cables, that’s 5-10k pairs, in 32U. That doesn’t work at all. It’s light (ha, pun) on details for what the alternative waveguide is, though.

Just getting VCELs to 25G per lane would be nice, though, if you can match current prices. Upgrading to 100G-SR4 on the same cable plant would be nice.

replies(1): >>45078863 #

nullc ◴[30 Aug 25 23:17 UTC] No.45078863[source]▶

>>45078788 #

> If you’re using fiber optic cables, that’s 5-10k pairs, in 32U.

not with 4 or 12 core MCF!

replies(2): >>45078906 #>>45079728 #

1. deepnotderp ◴[31 Aug 25 02:12 UTC] No.45079728[source]▶

>>45078863 #

MCF has a bunch of challenges, eg no good pigtail connector, need for rotational alignment, inability to radix (MCF is great for point to point, less good if you want to fan out from one chip to multiple chips), etc

And then even after all that, it’s still 1-2 orders of magnitude lower density than waveguides

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Can cheaper lasers handle short distances?