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Comment Re:Good Idea, and a Possible Modification (Score 1) 120

"no real attempt to move the launch platform up to 80,000 feet or so using gas balloon technology. I would have thought this would be feasible, and could result in a substantial fuel saving."

The fuel cost of a launch to low orbits is not for the altitude, but for gaining enough speed to stay in orbit, i.e. about 8 km/s. The gravitational energy becomes significant if you need altitudes comparable to the earth radius (6400 km).

Comment No? (Score 1) 196

It tried to RTFA, but it was in Japanese! I thought Japanese didn't have a word for "no":

Japanese also lacks words for yes and no. The words "hai" and "iie" are mistaken by English speakers for equivalents to yes and no, but they actually signify agreement or disagreement with the proposition put by the question: "That's right." or "That's not right.

Comment Re:Is there any value in studying this? (Score 5, Informative) 44

studying an encryption scheme that is widely considered completely and irreparably broken?

All known issues with RC4 have to do with statistical biases in the first bytes of the key stream, in particular the first 256 bytes (this paper also mentions a significant bias at byte 258). As far as we know, all issues with RC4 are avoided in protocols that simply discard the first kilobyte of key stream before starting to apply the key stream on the plaintext. SSH does this (discarding the first 1.5 kiB IIRC). For WPA I can imagine that this workaround would have an unacceptable performance penalty on small data packets. For some reason, this approach was never implemented for TLS/HTTPS or WPA.

So why would one be interested in RC4? It's significantly faster than AES when run on processors that do not have hardware AES support. If I use scp and rsync-over-ssh to copy files to devices like a Raspberry Pi or my home server which runs on a low-power VIA processor, it's a big difference (aes versus arcfour), something like 4 MB/s versus 8 MB/s. Here are some benchmarks: openSSH cipher benchmarks.

I keep my eyes open for papers like this, in particular I check whether they make statements on weaknesses after the first kilobyte of key stream.

Comment Re:Hotmail's whitelist is an effective system (Score 1) 55

"Congratulations, you're a spammer."

You're jumping to conclusions. There are perfectly legitimate reasons for that kind of mail volumes, such as administrering mail servers of a company that handles customer support tickets or a web shop with order confirmations, shipping notices, and invoices (3 emails per order). It could also be an opt-in mailing list.

Comment Re:Photos still stuck in... (Score 3, Informative) 177

Problem is that these photographers are still stuck in the 20th century, and will give you a printout.

They changed the photo business in the biggest attraction park in the Netherlands, quite recently. They used to charge EUR 10 or so for a single printout. Now they sell you a 4 GB USB stick for EUR 20 which you can load with up to 15 (?) photos and which you can re-use on a next visit until some expiration date. And afterwards, you can use it as any other USB stick. I thought it was pretty reasonable. It was the first time ever I paid for photos in an attraction park.

Comment Re:GMOs have so many different problems (Score 1) 188

"I will agree that with the rate of technological change today, the current 20 year protection is ridiculous. Technologies are typically woefully outdated by the time patents expire. IMHO patents should last significantly less time than currently (say 5 years or so),"

A farmaceutical product can well take much longer than that between the time the compound was discovered and the time it has passed all clinical trials and gets approval.from the authorities.

I work in the high-tech industry, where it can easily take 5 years between the first conception and the actual sale of the product. Only for small, incremental changes of existing technology, we sometimes get below 2 years.

The patent system is broken IMO, but not because of the 20-year term. The threshold for patentability is way too low IMO. Every big player in the industry is aggressively patenting every little idea just because the others do the same and nobody wants to be bitten in the ass by a competitor's patent or a patent troll. (I am personally in a strange position,since my employer provides various incentives to generate IP, so I end up contributing to the systemic problem.)

Comment Re:Bullshit (Score 4, Insightful) 401

"The case in question is regarding defamatory comments posted to a site that the victim went to court over. The courts ordered that the content be taken down. The lazy assed website owners took SIX WEEKS to remove the content."

No. RTFJ(udgment), under the chapter "FACTS".

The comments were removed the day the complaint came in, at which time the comments had been online for 6 weeks. This happened in 2006, by the way. The website had a mechanism for users to flag comments; apparently the complaining party had not used that and demanded monetary compensation at the first contact.

The judgment is surprisingly legible, though rather long. Much better than the average EULA. I didnn't read past the description of initial events. I'm sure that it also explains why this particular website owner was held responsible.

Comment Re:NSA removing PRISM taps (Score 4, Informative) 168

While the owner is detecting the problem, isolating where it is on the fibre and sending out crews to fix it, the tap is applied in the second location, along with suitable repairs and whatnot.

I'd say that finding out where it is on the fiber is done by measuring the time it takes for a light pulse to reflect off the disturbance and converting that to distance. If the distances measured from both ends of the fiber do not add up to the length of the fiber, the owner of the fiber should get very suspicious. Would the eavesdropper take that risk?

According to a friend of mine who's into fiber optics, tapping a fiber can be done without interrupting the fiber. If you bend a single-mode fiber, it will leak light, which is relatively easy to capture. The resulting signal loss of a few dB is likely to go unnoticed.

Comment Re:Weak encryption = No encryption. No exceptions. (Score 1) 108

"You cannot make encryption only weak for the "good" guys. It simply doesn't work that way and wishing will not make it otherwise"

The broken elliptic-curve random generator actually had such a feature: it was likely that the NSA has a secret key that could be used to recover the internal state of the random generator. However, recovering this secret key was impossible for all practical purposes.

For encryption, one could demand that encrypted data includes a header that contains the key to decrypt the data, that key being encrypted using a public key provided by the "good guys". Voila, the good guys can decrypt your data and the bad guys cannot.

Comment Re:Fear of guns (Score 2) 535

Even if you are not very familiar with guns, you'd have to be pretty obtuse to mistake [a stormtrooper gun for a 9 mm gun]. If you can't tell the difference between them, then you probably wouldn't be able to distinguish a gun from a stick.

Of course, it's obvious to anyone that a stormtrooper gun is not a standard 9 mm gun. But that's not the point. The question is whether it's reasonable to assume that anyone would be able to tell in an instant that there exists no firearm that looks like a stormtrooper gun. I would surely be scared as hell if a stranger pointed that thing at me.

Here in the Netherlands, it's illegal to carry something in public that could reasonably be mistaken for an actual firearm. That's why toy guns here are invariably made of bright-colored plastic. I believe that this policy has prevented quite a few (fatal) misunderstandings.

Comment App permissions (Score 1) 106

"Feature request: manually set app permissions please."

From TFA: "You don't have to agree to permission that don't make sense to you. Now, apps will ask when you first start them which device functions they want access to. You can pick and choose on a per-app basis what is permissible."

It's about time...

Comment Re:Computers Kill Trees (Score 1) 128

Your EPA document is about sequestration rates PER TREE in (sub)urban setting. Under such circumstances, the CO2 sequestration rate would depend mostly on the amount of sunlight that it can capture, which increases as the tree grows. A typical urban tree looks like a short stick with a strongly branched green ball on top.

In a production forest, trees are planted closely together and compete with each other for light. You'd expect the photosynthesis rate per unit of ground area to level off once a full leaf coverage is reached, which could well happen within 20 years. My idea of a production forest is lots of tall stems with little branching, most leaves near the top, and not enough light to support plant growth at ground level.

Secondary effects could be that the trees waste more energy on forming new leaves every spring that capture a smaller and smaller fraction of the sunlight as the competition for light increases. That could well lead to a reduction in net sequestration rate over time.

To me it seems plausible that you're both correct, but comparing apples and oranges.

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