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Comment It has to be really cheap to succeed (Score 1) 48

This service has to be really cheap and fast to succeed. Iridium and GlobalStar already offer a satellite-based service. Iridium really does cover the entire planetary surface; GlobalStar has most of the planet, but not the polar areas. So it's all about being price-competitive.

Comment Not distributed (Score 4, Interesting) 76

I'm not qualified to judge whether it's secure, but it's not distributed. "Each user is provided by PKG with a set of private keys corresponding to his/her identity for each node on the path from his/her associated leaf to the root of the tree via a secure channel as in IBE scheme." So there's a tree of all users, maintained by somebody. I think; the paper suffered in translation.

Comment Re:What has changed? (Score 1) 221

There was a time that a citizen could walk right up to the White House.

That lasted until WWII.

Until the 1980s, anyone could enter the Pentagon and wander around the corridors. (George C. Marshall, Army Chief of Staff, decided during WWII that there was no way a building with as many people as the Pentagon could keep spies out, and requiring badges would give a false sense of security.) In the 1960s, anyone could enter most Federal buildings in Washington, including the Capitol and all the House/Senate office buildings, without passing any security checkpoints.

Comment The President was out. The Secret Service did OK. (Score 3, Insightful) 221

It was a Friday evening. The President had left for Camp David earlier, and his main protective detail went with him. Most staffers had gone home. The guy got just inside the outer doors, where there is a security checkpoint, before he was tackled.

The Secret Service made the right choice not shooting the intruder dead on the lawn. They certainly had the capability to kill him. They would have been heavily criticized, with pictures of the dead body on national TV.

On September 12, a man wearing a Pokemon hat and carrying a stuffed animal jumped the White House fence. He was tackled and arrested. Should he have been killed?

Comment Re:Comparable? Not really. (Score 4, Informative) 126

When someone buys a share in Apple, they actually get an ownership share in Apple.

Apple, yes. Google or Facebook, no. Google and Facebook have two classes of stock. The class with all the voting rights is in both cases controlled by the founders. The publicly traded shares cannot outvote them, even if someone bought all of them.

Until recently, multiple classes of stock were prohibited for NYSE-listed companies, which tended to discourage doing this. (The classic exception was Ford, which has two classes of stock, the voting shares controlled by the Ford family. This predates that NYSE rule.)

This matters when the insiders make a big mistake and the stock starts going down. There's no way to kick them out.

Comment Re:Was it really so bad? (Score 1) 392

> church...index cards and toilet paper

Exactly. Those xians are so stupid as you note. They are all racist and want to murder us minorities. That is the way of their kind. They flood the streets with guns to kill young black men, and they know that by denying them ER care that more of us will die. That is their ultimate plan. They are denying us healthcare in order to kill us.

I... think you're focusing on a minor bigotry of the GP, which was not really related to his main point.

Comment Crash not computer-related (Score 5, Informative) 179

The Red Line crash was not computer-related. The signalling system for the Washington Metro is a classic electromechanical relay-based system. Just like the New York subways. The Red Line crash was caused by a failure of a track circuit for detecting trains, trackside equipment using an audio-frequency signal sent through the rails and shorted to the other rail by the train's wheels. All those components are pre-computer technology.

As with most railway systems, manual driving isn't enough to prevent collisions, because stopping distances are often longer than visual distances. That was the case here.

The Washington Metro had been sloppy about maintenance of trackside equipment. They do have a central computer system, and it logs what the relay-based signal systems are doing, although it can't override them. They had logs of previous failures, and should have fixed the problem.

Comment Re:White House (Score 2) 138

the US Government use UCAVs to keep the airspace around DC clear.

Actually, the current response to airspace incursions in the DC area is an F-16 and a Coast Guard helicopter. The F-16 is in case it turns out to be hostile, and the Coast Guard helicopter is for the usual case, which is a clueless VFR pilot who needs directions. This happens several times a week. The FAA now insists that all pilots operating within 60 miles of DC (actually 60NM of the DCA VOR) take this online course. Amazingly, there are still clueless pilots wandering into this airspace, although fewer than a few years ago.

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