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0 pointslondons_explore5y ago0 comments

People realised that you maximize the throughput of the raw medium if you push it hard enough it has a high error rate, and then correct those errors.

Error correction tech has reached information theory perfection (if you ignore latency), so it always makes sense to use as much of it as possible. In the future I wouldn't be surprised to see bit error rates pretty close to 1:1, and massive amounts of FEC.

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jpmattia5y ago

> People realised that you maximize the throughput of the raw medium if you push it hard enough it has a high error rate

When?

FEC has been used in optical systems for decades. The undersea fiber guys have been using it in production at least since the 90s, for example. So I'm a little amazed that decades went by before someone noticed that you can throw BER out the window for the components and drivers to improve the overall system BER.

londons_exploreOP5y ago

From systems pre-error-correction... Think RS-232 serial for example... No error correction there, so people typically don't push hardware too close to the limits of bit rates because every bit error will cause some breakage. Even today, a lot of modern devices talk with RS232-like protocols, and none of them have even parity bits - it's just assumed error rates are so low as to be zero across the useful life of the product.

wmf5y ago

It probably used to be cheaper to use high-quality optical components until Moore's Law brought down the cost of FEC enough.

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