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Comment Re:But where/when does one explicitly learn securi (Score 1) 809

I grok the snark, but in my experience people who take their own initiative on learning and personal development gain 10x more than people who get sent to some boot camp or seminar on their employers dime. If you are learning something useful it all comes back to you in a future paycheck anyway. "I haven't been trained on this" is generally an excuse I hear from people who wouldn't know their ass from a hole in the ground even if they did attend a 3 day ass-recognition boot camp.

Comment Re:Maybe stupid question of the day (Score 1) 64

This could be a low power way to sync your phone with your watch or your watch with your TV or your TV with your robotic vacuum cleaner. Wifi has a lot of complexity built in, and uses a lot of power. This could also have some niche applications in noisy environments like electrical utilities.

Comment No applications in Telecom (Score 2) 64

Before anyone says anything about fiber optics, this is useless for any application other than short range wifi/bluetooth replacement type technologies. The attenuation of light in fibre has a minimum around 1550nm, infra-red. Shorter wavelengths experience high attenuation due to scattering. Longer wavelengths have more absorption.

Comment Re:how do they do it today? (Score 1) 59

The receive sensitivity on common '10G' DWDM optics is frequently down to -24 dBm or lower. That's less than a hundredth of a mw. So from that perspective, that +0 or +3 dBm is rocket hot. 100G optics aren't quite as sensitive, but still down to -14 or -17 or so depending on the specs.

Comment Re:how do they do it today? (Score 3, Informative) 59

This sort of thing is measured in dBm to make the math easier. Decibel Milliwatts, where 0 dBm = 1 mw and it's a logarithmic scale up and down from there.
Individual channels are on the order of 0 to 5 dBm, or 1 to 3 mw. The composite signal coming out of an amplifier, which consists of multiple channels, is on the order of 20 dBm depending on how many channels are active and what the reach of the amplifier is. That's about 100 mw. Definitely a laser safety concern, but not military style death ray.

Comment Re:how do they do it today? (Score 1) 59

There are, which is why the electricity is at very high voltages to overcome it, which is why it attracts sharks. I'm more of a terrestrial guy, but if i remember correctly what they do is apply a very high + voltage on one end of the cable and a very high - voltage on the other end, and the amplifiers are powered in series inside of 'festoons' on the bottom of the ocean.

Comment Re:how do they do it today? (Score 4, Informative) 59

But there are still going to be amplifiers. They are referring to eliminating transponders, which we already don't use for modern sub-sea links. This is basically just 16QAM, but instead of using 4 symbols over 1 frequency, it's 2 symbols over 2 frequencies tightly spaced together. It's been understood for a while that widening the channels was probably the only way to go beyond 100gbps for a transmitter/receiver.

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