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Arithmetic Encoding Compression.  Has anyone heard of this?

I remember many months ago there was a discussion about compression algorithms like LZW.

I have a snippet of C code for a compression encoding method called arithmetic encoding.  The code is actually quite small.

If anyone has already created an FB version of this I'll discard my efforts.  If not I'll finish it up and present it here.  I'm curious to see how effective it is compared to the more common algorithms.


Separate topic:

I'm also quite interested in encryption techniques.  I'm going to buy 'Applied Cryptography' <http://www.amazon.com/exec/obidos/ASIN/0471117099/qid=1004081902/sr=2-1/ref=sr_2_15_1/107-8267062-7502145>

In the meantime, here is a website with some good information on security and related topics.

<http://www-105.ibm.com/developerworks/papers.nsf/dw/security-papers-bynewest?OpenDocument&Count=500>

I mostly started looking at this because of Ken's Scramble example.  I'm wondering if there is a better scramble algorithm than XOR

From the IBM security site:

>In fact, most home-grown algorithms we have seen involve simply XORing the data with some constant, and then performing some other slight transformations to the text. This sort of encryption is almost no better than no encryption at all.

Obviously, Ken wasn't trying to make an encryption function but the better Scramble scrambles, the better it will function.

One other note from the IBM site:

>One sweeping recommendation applies to every use of cryptography. Unfortunately, it's one that is very often ignored by software developers -- never roll your own cryptography.

The Applied Crypto book has all the major algorithms but I wonder if there are any open-source ones on the internet?
-- 
Heather Donahue
--
non sum qualis eram