Group items tagged

For longer ciphers, Kasiski analysis is useful for determining possible keywords using a modified frequency analysis and repetition analysis. This is an online tool to find repeat sequences in a ciphertext, and can be used to quickly decrypt a Vigenere ciphertext.

Cryptanalysis and Frequency Analysis

An in-depth description of Julius Caesar's shift cipher and how it works. Also shows how to use frequency analysis and chi-square values to quickly break the cipher.

Just like in Little Brother! Schneiner responds to this article here: https://www.schneier.com/blog/archives/2008/09/gait_analysis_f.html

Encrypted analysis of data in the cloud would allow secure access to sensitive information.

Homomorphic encryption is pretty amazing. What they're proposing in this article is a bit like having a computer analyze an encrypted novel and determining which sentences were grammatically incorrect--without even knowing what the plaintext sentences were!

I'm just going to resubmit the bookmark directly to this page so I'll be sure it ends up publicly in the group. This wasn't mentioned in Singh chapter 2, but it was created around the time period discussed in the chapter. (Plus, it's one of my favorite articles I've read in Wired so I really wanted to use it as a bookmark.) The article discusses the strategies used to break this cipher, some of which, such as frequency analysis, we have talked about in class. It's also just fascinating to read about the Oculists and their history.

A little progress on the mysterious Voynich manuscript...

Bernoulli numbers are a sequence of numbers important to the field of number theory, trigonometric expansions, and analysis. Ada Lovelace wrote a theoretical program to calculate these that would work on Charles Babbage's unfinished Analytical Engine. It's pretty interesting how Lovelace was a "leading figure" in the now massively male-dominated computer programming field, but didn't receive recognition for her work until fairly recently.

See also Riley's bookmark and my comments on it.

Interesting how this article talks about the gait analysis being used for catching terrorists, while in Little Brother, it was used to keep track of the high school students. The technology is not quite ready to be used, but seems to be much more reliable than the gait trackers in the book.

Georgia Tech Research Institute is making gait recognition technology a reality. "The ultimate goal is to detect, classify and identify humans at distances up to 500 feet away under day or night, all-weather conditions. Such capabilities will enhance the protection of U.S. forces and facilities from terrorist attacks."

Here's the paper that Robert Ward of Maryland shared with me via email last year. The stats look solid to me, although I didn't check his p-values. Let me know if you work this into any of your projects this fall!

What specific legal frameworks are relevant to a discussion of mass surveillance?