Sometimes I'll spend hours searching books and online to figure out how to do something that's ends up only being a couple lines of code. So if I can help anyone, why not?

Establishing long distance 802.11 links

My original title for this paper was “Quantum Electrodynamics, diffraction, the Huygens-Fresnel Principle, earth bulge and their effects on the Fresnel Zone,” but I thought that was a bit much. Plus I was afraid it might scare some people away. This paper does assume some RF competence on the part of the reader, and at least a basic understanding of algebra. As my original title indicates the actual scope of this article is much more refined than the revised title would lead one to believe. I will not be discussing the finer points of establishing long distance connections from start to finish. This paper’s main focus is on the Fresnel Zone (Pronounced Fra-nel btw).
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A Crash Course in Cryptography Part I – A History of Cryptography

This entry is part 1 of 2 in the series A Crash Course in Cryptography

Welcome Ladies and Gentlemen to A Crash Course in Cryptography. The words of importance here are “A Crash Course”. This will not be a terribly advanced course, it’s designed to introduce people to some of the concepts and methodologies used in Cryptography. There will be some technical talk but mostly the conversation will be focused at the conceptual aspects. Today’s class specifically will be aimed at getting people familiar with terms used in cryptography. We will also be explaining why cryptography is important both now and in the past.
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Spread Spectrum and Modulation/Encoding Techniques used in 802.11 Wireless

The goal of this paper is to educate those curious on how information is sent in wireless LANs. This paper is about the physical way the signal is sent, that is to say we will not be preforming a dissection of the 802.11 protocols but rather the manner in which the ones and zeros make their way through the air. We will be covering the various spread spectrum technologies used such as FHSS, DSSS and OFDM. Beyond the spread spectrum technologies we will also be discussing Barker Codes, CCK, DB/QFSM and other fun stuff, so sit back and enjoy the ride.
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The Joy of Mounting

The topic of mounting is a broad one. An individual need only look at the mount(8) man pages, one of the largest tomes accessible via man rivaling even ps. Read the rest of this entry »

Cron: Making Computers Work For You

So, you want to make your computer start doing stuff for you with out even having to ask? We all know the myth that computers were created to preform the menial tasks humans would get bored with. The problems is they often *create* more than they solve. How often have you had to do something and though, “If only the computer would just take care of this for me every Sunday.”
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