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What the hell is the problem anyway? For fifteen minutes at the beginning and end of a flight you can't use your iWhatever or eWhatsis. Big deal.

Because if these tiny sources (cube law, hello?) of random RF noise really were a problem, they don't suddenly become less of a problem while flying in the air at over 10,000 ft. Or when flying through or even remotely near a thunderstorm that produces many times that RF. Heaven help the poor pilots that get painted by a military radar or even the radar from the airport.

It's not like an airplane needs reliable controls when say, hurtling through the air at a couple hundred miles an hour over populated areas, is it?

At the best we can blame the aircraft designers for not doing their due diligence in properly shielding the route between servos and controllers and cockpit. After all, shielding is precious weight in paying passengers you'd have to give up in fuel. And we obviously don't have lighter weight communication medium that isn't RF sensitive.

I, for one, fear the eventual introduction of the Taiwanese semiconductor beetle. Not only do its feeding tunnels encourage premature ion migration, it carries the fungus that causes bit rot.

Actually that fungus that causes bit rot is caused by the lack of lead in the solder that causes "whiskering". Lead kept the whiskering down in circuits; it's removal means now that many forms of electronics will simply "wear out" over time. The whiskers are little tiny cylinders of tin, a conductor, and they tend to grow on new circuits over time. http://archive.evaluationengineering.com/archive/articles/0606/0606lead-free.asp has a good description and accompanying photomicrographs. Lead has been legislated out of solder by RoHS (Reduction of Hazardous Substances) acts in various countries under a variety of names.

Arguing this point with you is useless. It's like any other issue out there: You can usually distill the issue into two camps. Each side opposing one another with thier ears closed and mouths running with neither side willing to budge.

I will say this though -- if what you are saying is true, which I honestly dont believe (the heat from batteries are another popular excuse) then:

Why did ANSI and IEEE adopt a "Specific Absorption Rate" limit that was subsequently mandated by the FCC in order to limit the amount of RF absorbtion by cell phone users?

And how is that measured, you would probably not ask? Why that would be with a calorimeter used to measure the change in soft tissue temperature.

The heating issue is real. Studies have found that the highest absorbtion rate is where? In the ear.

your move.

I cite my references, how 'bout you?

The use of a hands-free headset partially reduces the electromagnetic-field strength at the head.1 However, the cable not only transmits the intended low-frequency voice signal, but also couples a portion of the cell phone's RF energy onto the cable and subsequently to the user's head. The localized field strength of this RF energy depends on the frequency (either 900 MHz or 1,900 MHz), the length of the cable (normally about 25), and the standing waves this creates.

That's Bytes, as in 8 bits. A 100 Mbit/sec NIC is only 12.5 MBytes/sec.

When I first read the post, I got pretty excited. Dreams of cheap clustering for scientific applications danced in my head. No more need for Myrinet, no Dolphin, just Firewire and Beowulf!

Then, I read some performance metrics on Firewire. High bandwidth. High latency. Doh! The fairies stopped dancing for joy.

The problem is that in scientific computing, the time it takes for one node to say I need that data to another node, and actually get that data determines the performance of many more apps than does the speed of the CPUs.

So, until a cheap, low latency solution for communications comes by, real clusters will be communicating over Dolphin, Myrinet, or some other propietary technology.

Tony