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Comment by PaulHoule | Hacker News Reader

Telcos hate low latency. High latency is in their DNA. Nobody has ever been able to sell low latency except to HFT people, and until they started asking, nobody knew what a circuitous route the cables took from Manhattan to New Jersey.

The first research project Bell labs did was a test to see how much latency they could get telephone users to tolerate.

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I would like to see a source for that, because this makes no sense

Latency in analog circuits is a natural product AND very difficult to change either way

In digital circuits you might have things adding latency like encoders and filters and some effects of network and packaging of voice data

Unless you're blaming AT&T for not being able to go faster than the speed of light

It makes sense just fine. The research about latency tolerance informed the design constraints for packet-switched digital phone networks, which had been proposed since the 1950s and began to replace POTS in practice in the 1980s (e.g. System X in London in 1980).

Latency requirements constrain routing and buffering specs. Packet switched voice could not work until the system could meet human tolerance of latency.

While that is true, at a certain point, more latency in a working system costs money, especially at the earlier switched systems

But yeah, they needed to do a research about it, but I would doubt "The first research project Bell labs did", since Bell Labs predates digital phone networks

Sure, but no-one is ever talking about deliberately over-long latency. There's a sweet spot where packet-switched is fast enough, while cheap because of shared bandwidth and routing flexibility. It costs more to go faster, but it's game over to go slower than humans will accept.

And it's unlikely that the poster was referring to direct (non-packet) connections since these have been rare for a long time.

> The first research project Bell labs did was a test to see how much latency they could get telephone users to tolerate.

Do you have a source for that? I genuinely enjoy reading about things like this.

I agree with __john ; reading about this stuff is cool. Source please?

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