Saturday, June 21, 2008

noise

Mkay... some ex-convict, who also happens to be famous, is denied entry in the UK. The UK rules, I love the UK. I fully agree with the British Border Agency: "we continue to oppose the entry to the UK of individuals where we believe their presence in the UK is not conducive to the public good". (In one way or another.)
Mkay... stupid mascot causes floods, or maybe it's just that Chinese symbolism is dumb and outdated. Also, those mascots are hideous. While we're at it, why don't we just shift all those eights a little bit? (pausing for a few moments) Aha! so that's how one transmutes prosperity to death and darkness to light etcetera. Interesting, I've learned something today.
Mkay... A lot of time has passed and people are still discussing Pluto. It's still amazing to see how much time and energy people invest in such irrelevant matters. Gravity Probe B canceled on the home stretch? Anyone? Bah! Pluto! You know what? Fuck Pluto and fuck the Hubble telescope for not being able to snap a photo of Pluto that's more than six pixels wide. We have pictures of Neptune, both from deep-space probes and from that orbiting piece of scrap that's been launched in space without being properly tested first, but we have great difficulty in obtaining pictures of Pluto. We also know there are bodies larger than Pluto beyond it and we don't call them planets, but we're still giving a shit about that piece of crap that can't even hold it's own orbit. We've failed as a race.
Mkay... crazy fanatic preacher admits to inscribing "an X, not a cross" on students' arms. A-ha! So not all terrorists are Muslim! We've learned something today, haven't we? The interesting thing is that he used "a science tool known as a high-frequency generator" to do what he did. This warrants further comments:
1. On the one hand, what he did is obviously wrong on many levels, but why the hell did he have to use an RF generator? I said this before in a previous post, concerning laser pointers: a knife can be used to prepare food, to heal people through surgery, or to kill people. Are you ready to ban knifes just because they can be used to kill people? I don't want to live in a world where I'm not allowed to use an RF generator because it can be used to burn people or cause interference. I know the article isn't about this, but I feel the problem needs to be raised. There also remains the question: why the hell use an RF generator, which is intrinsically evil and satanic as per the Bible, when there are matches and cigars and stuff available?
2. On the other hand, the guy might actually earn some bonus points for his technique. I mean, that's being inventive. It has hack value. For instance, if I had an RF generator and wanted to draw stuff on my skin, I'd certainly consider using it for that purpose, but maybe I wouldn't be thinking about this, had it not been for this guy's misdeeds.
Mkay... I was simulating some low-power wireless network and it wasn't working. No packets would get from one node to another. After countless hours of digging through the sources (I was lucky I had the sources), I found out that the simulated noise what at a constant level of plus 127 dBm. Sadly I can't give a fancy link to Google Calculator because it doesn't seem to know dBm, but I can tell you that's huge. I mean just look: Wikipedia has tables that speculate on how a hundred yottameters look like, but its dBm-to-watts table stops at 80. To get 127 dBm of noise power, or 5 gigawatts, you'd have to be inside a fusion reactor, or better yet, a hydrogen bomb. Well, the radio simulator would detect a collision at anything above -70dBm (like the physical chip does), which, as the Wikipedia table states, is quite a reasonable value. Anyway, fuck that, and fuck the fact that the interface for specifying noise in the radio simulation changed from TinyOS 2.0.0 to 2.0.1, breaking compatibility and silently failing (at least in the code I was working on, which I admit is... particular). You know what? Fuck bad programming, and fuck such a lousy sense of physics. This however raises the question: If I wrote a simulator from scratch, would I give debug warnings when parameters go haywire? Of course not, if only because there is no clear threshold after which a value can be safely identified as being totally insane. Maybe I should submit a patch that simulates the RF chip instantly vaporising into a greenish puff of smoke, so hot that even all the magic's gone away. I mean, if they simulate noise and attenuation and collisions and bit errors, why not?

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