From Newsgroup: comp.misc

YourCOd think lasers are so commonplace now, itrCOs hard to imagine that
they might be considered rCLexpensiverCY for some applications. But here Microsoft is proposing using LEDs instead of lasers to transmit data
along optical cables <https://www.tomshardware.com/tech-industry/microsoft-expects-to-commercialize-microled-datacenter-cables-by-late-2027>.

It takes hundreds of parallel LED channels to match the speed of a
single laser channel -- thatrCOs how slow the LEDs are. Yet somehow this
ends up more energy-efficient (what about cable cost?).

I canrCOt help feeling this is backwards. Consider what happened when
PCI expansion buses were replaced with PCI-E: PCI was a parallel data
bus, while PCI-E is serial, transmitting fewer data bits on each clock
cycle.

But it works, because the parallel bus was prone to rCLclock skewrCY, that
is, as the clock speed went up, it became more difficult to keep the
different signal bits synchronized as they got from one end of a
connection to the other. The lack of this problem is what allowed the
serial bus to crank up to much higher clock speeds, to make up for its serial-ness, and then some.

It seems to me the same phenomenon will apply at some point with
MicrosoftrCOs massively parallel optical bus.
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