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Comment Re:Tape backup - (Score 1) 215

LTO almost always achieves a 2:1 compression using SLDC unless the data is pre-compressed or particularly random resulting in no compression. For the purposes of photos or video a 2:1 ration would be a safe assumption to use.

LTOs will read their own generation and the tapes of 3 previous generations. They will also write to their own and the previous generation of tapes. It is this strict adherence to a standard which makes them such great backup options.

I don't understand what you mean about drives with 1 digit indicator? Given HP and IBM are both primary contributors to the LTO project and have access to the same materials I don't see much in the way of difference.

Comment Tape backup - (Score 1) 215

Go onto ebay and buy an 2nd hand LTO3 or LTO4 tape drive for $150 - $300. Plug it in, write your files to the tape. For 2tb you would need 3 LTO3 tapes (assuming compression 800gb each). Take said tapes and drive them to another house.

Decide what timeframe of loss is acceptable. ie 4 weeks, 4 months, 12 months. That is you maximum backup cycle time. Every X period of time take a new set of tapes to your offsite backup location. Buy tapes equal to at least 3 full cycles, that way on your third backup trip you take the oldest set home and re-use them.

This is the process I use every 3 months and I have an HP Ultrium 960 sitting on top of my NAS. I also use your normal google drive type backup, but it is my second stage, rather than first stage backup. I'm not quite at the same size as you, 1.1tb, so it's 2 tapes not 3. I bought a box of 50 new lto3 tapes for $100.

Comment A few obvious corrections (Score 1) 49

First, DES is 56 bit (near enough 60). Triple DES as per first mode (the authorised standard) is 168 bits. The article fails to distinguish, implying the authors are just a little bit naff. 3DES seems to be quite safe, as long as not used in DES emulation mode. And who the hell emulates a mode that was broken in the 80s?

Second, Blowfish was replaced by TwoFish, ThreeFish and Speck. Skein, an entrant to the DES3 challenge, makes use of ThreeFish.

Third, the Wikipedia page states it has been known for a long time that weak keys are bad. This particular attack, though, is a birthday attack. You can find all the ciphers vulnerable or free that you should be using. Anything not on the list is something you are solely responsible for.


In other words, this information is about as useful as telling up that Model T Fords weren't good at cornering at highway speeds. Below are some links, I can't be buggered to HTML-ify them.


I do not trust most encryption software these days, but that's because programmers these days are sloppy and arrogant.

Comment Re:Ye olde 'negawatts' concept (Score 1) 153

California has given up on bringing new power generation online,

"Almost half of all capacity added in 2013 [across the US] was located in California." "Nearly 60% of the natural gas capacity [across the US] added in 2013 was located in California." http://www.eia.gov/todayinener...

California's total electrical generation capacity has gone from 55,344 MW in 2001, to 79,359 MW in 2015. That's an average increase of 1,644 MW of new capacity going online each and every year.


Energy standards in California call for 33 percent of the stateâ(TM)s power to come from renewables by 2020 and 50 percent by 2030, and so the state is building new wind and solar capacity as fast as possible. The recently built Ivanpah plant was the world's largest, and it's in California, not Arizona, for good reason.

In fact you can get a current list of power plants planned, under construction, and newly online, here:


Conservation is fine is a short-term solution to shortage - of anything - but in the long run there is no substitute for generating more power

California "has one of the lowest per capita total energy consumption levels in the country. California state policy promotes energy efficiency. The state's extensive efforts to increase energy efficiency and the implementation of alternative technologies have restrained growth in energy demand." https://www.eia.gov/state/anal...

Comment Re:HD on cellular (Score 1) 90

Do people really have to watch HD videos on cellular? Can't they wait until they get home near their WiFi's?

The cellular market is competitive, while the wired internet market is not. It won't be long before cellular internet service is cheaper than wired. In fact that has long since happened for light users.

You get charged about 3X as much for the same DSL speeds today as you did a decade ago. Cable has side-stepped the issue by just NOT providing lower speed service, and having their lowest-cost offering being $60/mo. Just look at Charter buying TW and dropping those pesky $15 service plans. And these are increasingly getting a low bandwidth cap, and customers are being forced into bundles.

Comment Re:We need this (Score 1) 231

My old flip-phone from 10 years ago lasted about a week on a single charge. Obviously, though, that's because it was doing jack-crap processing-wise compared to the mini-supercomputers we now all have in our pockets,

But how many years of process shrinks, improved LEDs, better radios, higher capacity batteries, etc., has it been since that flip phone was made? If manufacturers were chasing battery life, instead of biggest screen, thinnest phone and fastest processor, we could easily have smartphones running for several days between charges. Charging your phone twice a day has become the new normal, so nobody returns their power-hungry phones, and it's not prominently advertised, so manufacturers don't expect more sales from improving upon run-time and don't bother.

Think of it like web search engines just before Google came along... Everybody sucks equally, and one disruptive innovator jumping in could wipe the floor with everybody else.

Comment Re:Yeah, unfortunately we do. (Score 1) 376

Our deployment is all network based. It means that a lab full of machines can be reinstalled at the same time. Deploying a new iamge for an upgrade takes about 10 mins (including the walk around the room to reset each machine and change bios to netboot). I like our IT department - they do nice things.

When students visit me with work it is rare for them to even bring usb, normally it is sitting on dropbox or onecloud. Installing single one-off machines was the last use that I had for opticals, but now usbboot is quite stable and its less hassle to nuke a stick than it is to find a machine to burn a disc in.

Comment Re:Why wouldn't you? (Score 3, Insightful) 140

Because just maybe it could save someone. Because the person buried under the rubble was playing pokemon go and carrying at 16000mah battery pack. Because maybe the person has been turning their phone on for 5 minutes then turning it off when they have no signal. Because maybe the emergency workers in you area might be able to use it to communicate back to base where as for what ever other reason they couldn't have.

Comment Re:massive parallel processing=limited application (Score 1) 112

Also, there is caching, and also, some loads are heavy on longish FPU operations.

So... it doesn't quite work out that way. Also, multicore designs can have separate memory.

One example of multicore design that's both interesting and functional are the various vector processor graphics cores. Lots of em in there; and they get to do a lot of useful work you couldn't really do any other way with similar clock speeds and process tech.

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