This document is a gentle introduction to computational number theory. The plan of the paper is to first give a quick overview of arithmetic in the modular integers. Throughout, we will emphasize computation and practical results rather than delving into the why. Simple programs, generally in JavaScript, are available for all of the algorithms mentioned. At the end of the paper we will introduce the Gaussian Integers and Galois Fields and compare them to the modular integers. Companion papers will examine number theory from a more advanced perspective. ...

There are several reasons why one should prefer LaTeX to a WYSIWYG word processor like Microsoft Word: portability, lightness, security are just a few of them (not to mention that LaTeX is free). There is still a further reason that definitely convinced me to abandon MS Word when I wrote my dissertation: you will never be able to produce professionally typeset and well-structured documents using most WYSIWYG word processors. LaTeX is a free typesetting system that allows you to focus on content without bothering about the layout: the software takes care of the actual typesetting, structuring and page formatting, producing documents of astonishing elegance. ...

Video of a sandbox equipped with a Kinect 3D camera and a projector to project a real-time colored topographic map with contour lines onto the sand surface. The sandbox lets virtual water flow over the surface using a GPU-based simulation of the Saint-Venant set of shallow water equations. » @okreylos | youtube.com

» link | via reddit

El portal cautivo es el sistema que utilizan algunos establecimientos como bibliotecas u hoteles en el que la conexión inalámbrica está abierta (sin cifrar) pero para conectarse a Internet es necesario aceptar las condiciones de uso, o introducir una contraseña, en la página de pasarela que aparece cuando intentamos navegar. Este no es un artículo exhaustivo que muestre como saltarse cualquier portal cautivo sino más bien aquél que permite el paso de tráfico TCP por el puerto 53 (DNS). Lo que veremos aquí NO es un túnel DNS, que permite encapsular el tráfico TCP en paquetes de DNS. ...

El script Hash_ID.py, desarrollado por Zion3R, nos permite identificar los posibles algoritmos utilizados para crear un hash. En muchas ocasiones no se puede saber qué algoritmo concreto se ha utilizado, pero nos devolverá una lista de candidatos. El script compara el hash con el tipo de hash de algoritmos tales como: ADLER-32, CRC-32, CRC-16, DES(Unix), FCS-16, GHash-32-5, GOST R 34.11-94, Haval-160, Haval-192 110080, Haval-224 114080, Haval-256, Lineage II C4, Domain Cached Credentials, XOR-32, MD5(Half), MD5(Middle), MySQL, MD5(phpBB3), MD5(Unix), MD5(Wordpress), MD5(APR), MD2, MD4, MD5, MD5(HMAC(Wordpress)), NTLM, RAdmin v2.x, RipeMD-128, SNEFRU-128, Tiger-128, MySQL5 - SHA-1(SHA-1($pass)), MySQL 160bit - SHA-1(SHA-1($pass)), RipeMD-160, SHA-1, SHA-1(MaNGOS), Tiger-160, Tiger-192, md5($pass.$salt) - Joomla, SHA-1(Django), SHA-224, RipeMD-256, SNEFRU-256, md5($pass.$salt) - Joomla, SAM - (LM_hash:NT_hash), SHA-256(Django), RipeMD-320, SHA-384, SHA-256, SHA-384(Django), SHA-512, Whirlpool, etc. ...

Using vim is like talking to your editor in ’verb modifier object’ sentences, turned into acronyms. » yanpritzker.com

Like a lot of people, I have gone retro when it comes to editors, using Vim for most of my day to day work. I’ve been doing most of my development these days in a terminal window, logged directly into a VM where I test my code. » rc3.org

» dragonjar.org

The purpose of this document is multi-faceted. It is intended as: A gentle introduction to Upstart. A Cookbook of recipes and best-practises for solving common and not so common problems. An extended guide to the configuration syntax of Upstart. It attempts to explain the intricacies of Upstart with worked examples and lots of details. Note that the reference documentation for Upstart will always be the manual pages: this is merely a supplement to them. ...