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Comment: Mesh Design (Score 1) 53

I looked into this years ago from the physical layer support for full duplex and half duplex nodes (this was fun since I am a hardware guy) all the way up to designing a node addressing scheme which both helped with routing and allowed dynamic adding and deleting nodes (not so much fun but an interesting problem). The largest problem I found was scaling which would have required tunnels (wormholes) to high traffic endpoints or to shunt traffic around congested areas. Discouraging free riders was handled with public-private key enforced tokens; passing traffic for others (especially through tunnels) earned tokens (reputation) while generating traffic used them and there was a scaling issue there was well; in retrospect that part operated like a modern cryptocurrency. Like the original IPv6, all traffic was encrypted between endpoints by design. CPU and RAM requirements back then were non-trivial but ARM has come a long way.

Comment: Re:Except they just turn the power off (Score 1) 274

by Agripa (#49634499) Attached to: USBKill Transforms a Thumb Drive Into an "Anti-Forensic" Device

Explosives have the disadvantage of lacking non-destructive testing.

My favorite implementation for this sort of thing is a reed switch and externally mounted magnet. Tie the reed switch into the reset signal which is available in two different places, the front panel header and the power supply power good signal, and mount the reed switch so that either a magnet mounted to the floor or table under the chassis or inside of something sitting on the chassis is necessary for proper operation. The reed switch could also be used to disable a USB port though so operation would be through USBKill.

Comment: Re:Sort-of-worked. (Score 2) 49

by Bruce Perens (#49633129) Attached to: SpaceX Launch Abort Test Successful

What I am getting from the videos is that this test was a success but that there was indeed an engine failure and the system recovered from it successfully by throttling off the opposing engine. There was less Delta-V than expected, max altitude was lower than expected, downrange was lower than expected, and that tumble after trunk jettison and during drogue deploy looked like it would have been uncomfortable for crew.

This is the second time that SpaceX has had an engine failure and recovered from it. They get points for not killing the theoretical crew either time. There will be work to do. It's to be expected, this is rocket science.

It sounds to me like the launch engineers were rattled by the short downrange and the launch director had to rein them in.

Comment: Re:15 co-authors (Score 1) 186

by pla (#49632443) Attached to: 17-Year-Old Radio Astronomy Mystery Traced Back To Kitchen Microwave
"So, Dr. Flyskippy1, how many papers did you get published this year? Oh, only eight? Yeah, we need you to move out of the corner office next week to make room for a star postdoc who helped solve a radio astronomy mystery that stumped you tenured geniuses for the past 17 years. No hard feelings, right?"

Comment: Re:Surface? (Score 2) 132

by quantaman (#49632423) Attached to: NASA Will Award You $5,000 For Your Finest Mars City Idea

So you want to put the people underground where they'll be safe, and their source of food and fresh air (the greenhouses) where they're going to be, as you yourself say, vulnerable.

The greenhouses need to be underground as well. So does the power generation, which means a fusion plant. Good thing they're only 20 years away, just like they were 20 years ago.

You can put greenhouses above ground. Just make sure you have an underground failsafe and enough emergency reserves to make it through a disaster.

Even then it's probably not feasible. Look how expensive it is to go underground on earth, now consider how tough it will be on Mars when you're walking around in spacesuits and have to transport heavy duty excavation and construction equipment from earth.

More likely just put everything above ground and distributed. If an asteroid takes out a greenhouse or a house it's tragic, but it doesn't kill the colony.

Comment: Re:What about the law (Score 1) 99

by pla (#49631793) Attached to: Europe Vows To Get Rid of Geo-Blocking
if they know that they'll refuse to pay the 10 euro, that's how free markets are supposed to work,

No they won't - What you describe exists now, and we all merrily put up with it.

Hell, package forwarding from the US to Australia counts as its own niche industry designed exclusively to circumvent such BS. But while that may work for physical goods, it doesn't get around the same problem for virtual goods.

Comment: Re: Not forced... (Score 1) 251

by Richard_at_work (#49631735) Attached to: Uber Forced Out of Kansas

The NHS doesn't ask about the reason you ended up needing medical care, but you may find yourself being denied immediate access to treatments for non-life threatening issues if you indulge in activities which either hamper treatment or are exacerbating the issues - for example, smoking when being treated for COPD or lung cancer will get you into trouble, or being very overweight will cause surgery to be put off until you lose weight.

A mathematician is a device for turning coffee into theorems. -- P. Erdos

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