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

Anything modern is running EDFA's where fiber is doped with Erbium and a pump laser is mixed in they get about 40db of amplification with a 100ma laser. Great part is it's not signal speed dependent as it's an all optical all analog method. The old way was to put a receiver and transmitter coupled back to back used a lot of power and was specific to a speed.

Comment Re:Not my anecdotal experience (Score 1) 258

Well you can probably double your density moving to non hot swap 3.5's, making double the drives even on space. Now if I were going to do that I would mirror the raid sets anyways since power consumption of near line drives is pretty minimal.

Never seen much of a use of enterprise sata, I do use a lot of SAS with dual ports to separate raid controllers.

Comment Re:Power Costs (Score 1) 258

Well since they are not supposed to need to be hot swap you can get 12+ drive into a 1ru chassis with redundant power and a fairly beefy server. That is 3x the density of traditional 4 up front 1ru. Expanding to 2ru gives 12 hot swap 3.5's or 24 2.5 still 2x the density in 3.5's for non hot swap. Potentially even higher with 2.5's, though highest I find is 88 hot swaps in a 4ru or 22 per ru coupled with a rather beefy server.

Comment So they figured out raid z 3 with enough spares (Score 1) 258

To last all of 4 years, and need nearly as many hot spares as data drives. I guess the academics think they know something yet again. They took some dubious failure rates (backblazes use whatever is the cheapest consumer drive at the time and eventually stop buying the really bad ones (seagate 1.5 and 3tb looking at you)) and a rather optimistic transfer rate (200MBS) that assume all sequential reads. They failed to account for back plane, controller, and power assuming that those never fail. By their numbers you might as well run mirrored raid 5 or 6 with enough hot spares to make it between regularly scheduled tech visits. That give you the ability to split chassis and controllers along mirror lines. As to rebuilds we have better methods, predictive failure works well, ssd's make great caches while rebuilding etc etc. We also have less centralized options with distributed technologies that potentially scale better.

5 9's is not that hard of an objective when talking about raid sets, the tools have been there for decades. Sure you will never reliably reach it with a single path to anything, 5 minutes is not enough time for even a staffed site to remedy any outage.

Comment Re:Security is a yes/no question (Score 4, Interesting) 431

Incorrect, if they want access to your encrypted information they may get a warrant, you can then defend yourself against said warrant by contesting it, a judge might hold you in contempt for not giving up the keys (that is a contempt to try and make you comply not a punitive one so is only supposed to be until they figure out your not going to). This is not what they seem to be worried about.

They are worried about not being able to just take or use secret courts to access whatever they want. Pervasive encryption means they can no longer get all the info they want from the middle men who tend not to fight back much, use national security letters when even the secret courts wont give them a warrant. Having to use actual warrants served to the people effected who might fight them and use the media to shame them means they better have a good reason vs just fishing. You can also devise hardware and protocols that put a time limit on being able to decypt things that would limit the time held in contempt (simple one is a chip that holds the keys and erases them if it does not get a passcode every so often or looses power a basic extension on existing TMP).

In short you can have secure encryption that the government could force you to let them access. It's messy, time consuming, and does not always work.

Comment Re:A call for Write Protect (Score 1) 95

Trust as in how do you know jumping through those hoops stops the NSA? Maybe the use the secret courts to require a backdoor, maybe they alter the chips themselves.

The NSA etc needs a clear directive by the president and congress that this is not ok. As long as they get only a minor slap of do not do that again it will not stop.

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