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That is, if you are interested in the dry, technical details... ;-)

Here's the link to the paper:

As an Israeli citizen, I can tell you we are less a police state than what the US has become.
Yes we have national IDs and soldiers and security guards everywhere, but we have freedom of speech (at least to some extent). I can buy/rent a zone 1 DVD at any video store. I can publish code to decrypt DVDs without any limitation. I can practice cryptography without being targeted. In Israel, the policial and social pressure groups rule and not the corporations. Here we have strict laws limiting campaign contributions.

Now, which country is more free?

Sitting around sifting all these details through my head, it occured to me that all this AOL/Redhat talk might end up being super cool for the linmodem folks.

To spell it out, an AOL/Redhat OS will obviously need to work with the innumerable makes and models of modems lying about on joe-ueser's box. Of course this will mean a pretty wide base of drivers. Last time I checked the linmodem folks were making a good start with some drivers, but still pretty far from complete support for the umpteen million software modem brands.

Pure (another step-along) speculation for now, but I guess we shall see.

Israel A. Wagner's home page about Ants, Robots and Computation is here and it's a great and interesting compilation of data on this topic. Absolutely recommended.

3 different MiniPCI cards are available from IBM, and by default every ThinkPad comes with one, although which one depends on your exact model.

- Lucent/Agere Winmodem
- Intel Ethernet and Xircom modem
- 3Com Ethernet and modem

The Lucent/Agere winmodem and the Xircom modem part on the Intel combo card are almost identical, only the PCI ID is different (the Xircom modem part is just a rebranded Lucent/Agere part). Both MiniPCI cards work great with the Lucent WinModem drivers for Linux.

The 3Com card is more problemetic, both for Ethernet (although using a recent kernel should fix that) and for the modem part.

Check out http://linmodems.technion.ac.il/ for more information and drivers.

In short if your going to buy a ThinkPad or want to upgrade your modem-only MiniPCI card to also feature Ethernet, get the Intel card.

They're probably counting the separate red, green, and blue elements. These are separate pixels, as they are offset from each other. A special filter, known as a "demosaicing" filter, is required to correctly merge these offset images into the Y/Cb/Cr planes that are encoded in the final JPEG. The ratio isn't a factor of 3 as you might expect, as mosaic patterns tend to use more green than red or blue. (The patterns I've seen have 5 green to 2 red and 2 blue.)

This page describes mosaicing to some extent, in the context of reverse engineering a Kodak digital camera. This page at the same site offers some other details. And Ron Kimmel's page has some neat pictures showing different artifacts due to poor de-mosaicing.

I found some references. It is not possible to set arbitrary sequences. According to Breezecom (cached version here):

---quote---
For FHSS systems IEEE 802.11 defines 79 different hops for the carrier frequency. Using these 79 frequencies, IEEE 802.11 defines 78 hopping sequences (each with 79 hops) grouped in three sets of 26 sequences each. Sequences from same set encounter minimum collisions and they may be allocated to collocated systems. Theoretically, 26 FHSS systems may be collocated. However, as synchronization among independent systems is forbidden (synchronization would eliminate collisions), the actual number of systems that can be collocated is around 15.
---end quote---

I assume the three sequences are the ones I originally listed. If I'm not mistaken, it's considered a different "sequence" if you start in a different place. So:

1-5-9 is different from 5-9-1 and 1-5-9. So, an evesdropper would not be trying to guess a random sequence, he would just camp on one frequency, listen, and if a signal showed up he would start hopping. In other words, the 26 seqences vary only in time, so an eavesdropper only has to listen for a few seconds on one frequency to "check" all 26 sequences based on that set. Is that a fair assumption?

I also found a reference to an algorithm for determining which country you are in by checking which frequencies the AP broadcasts beacons on. In order for this to work, it requires the hop sequences to be well known for a given country. It's here

So, given this little bit of research, I still believe the claim that FHSS 802.11 is somehow more secure than DSSS 802.11 is basically crap. I would love to be proven otherwise.

Back in the 70's the NSA delayed the release of DES, for reasons which they could not disclose at the time.

NSA knew of a then-classified attack against DES known as differential cryptanalysis. NSA could not disclose why they delayed the release of DES, they could only say that they were still working on it. Lots of people speculated NSA was inserting a "secret backdoor", when actually they were ensuring the national standard for data encryption would be secure against even secret attacks than only NSA knew about at the time.

Of course, the complete design criteria for DES were not published at that time. Since not all of the steps in the algorithm seemed logical at the time, people got real suspicious. AES, on the other hand, is pretty straightforward.

For more background, check out this history of DES, or Eli Biham'sthese papers on differential cryptanalysys.
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For my thesis, I created a Web query system called ParaSite. The best introduction is the paper Squeal: A Structured Query Language for the Web, which I presented at the World-Wide Web Conference. Anybody is welcome to use my code, algorithms, or ideas.

See also WebSQL and W3QL, which also come from academia.

They did not invent this idea -- This comes from Dr Eli Biham, and was presented at the "Fast Software Encryption 4" (FSE4), held in Haifa, Israel in January 1997. Here's a couple links for info on bitslicing and DES stuff.

Birham's paper in .ps.gz format
An explanation of the technique and source

Looks like the Swedish team used these older ideas.

The second link also indicates that Distributed.Net clients use this method for DES, but no info on RC5.

Skipjack is not a good choice for several reasons:

1. Skipjack only has an 80 bit key. Even 3DES, at 112 bits, is better than that. Last year, Deep Crack broke a DES key in 56 hours, and the machine cost under $250,000. Assuming the government spent an even billion on a similar machine for Skipjack, they could brute force a key in 26 years. This is unacceptable for the truely paranoid. Rijndael, or any of the other AES candidates, has key sizes of 128, 192, and 256 bits. With a 256 bit key, a brute force search would require more energy than could be obtained by converting all the matter in the solar system.
2. Skipjack has a 64 bit blocksize. As long as you're going with a non-standard algorithm, you might as well use one of the AES candidates which all have 128 bit block sizes.
3. Skipjack doesn't seem to have been sufficiently overengineered to inspire confidence. A version of Skipjack reduced from 32 to 31 rounds can be broken slightly faster than through brute force (look here for details). This isn't a fatal weakness by itself, but it doesn't exactly look good either.
4. If you're woried about the government trying to read your mail, then not using an algorithm they came up with (and thus know more about than anyone else) is just plain common sense.