This project demonstrates the use of secure hash functions technique
to implement a file encryption / decryption system.
This implemented application can encrypt / decrypt multiple files
on the fly using a password. The password supplied by the user
is used as the source message from which the hash code (key) is
generated using the SHA algorithm. Then this key is used to
enctypted the data in the file(s). This key is stored in the
encrypted file along with the encrypted data.
This project demonstrates the use of secure hash functions technique
to implement a file encryption / decryption system.
This implemented application can encrypt / decrypt multiple files
on the fly using a password. The password supplied by the user
is used as the source message from which the hash code (key) is
generated using the SHA algorithm. Then this key is used to
enctypted the data in the file(s). This key is stored in the
encrypted file along with the encrypted data.
A pure python module which implements the DES and Triple-DES encryption algorithms. Triple DES is either DES-EDE3 with a 24 byte key, or DES-EDE2 with a 16 byte key.
Each exploration in this book is a mixture of text and interactive exercises. The exercises are
unlike anything you鈥檝e seen in other books. Instead of multiple choice, fill-in-the-blank, or
simple Q&A exercises, lessons are interactive explorations of key C++ features.
Playfair Cipher
1.not even the large number of keys in a monoalphabetic cipher provides security
2.one approach to improving security was to encrypt multiple letters
3.the Playfair Cipher is an example
4.invented by Charles Wheatstone in 1854,but named after his friend Baron Playfair
Playfair Key Matrix
1.a 5X5 matrix of letters based on a keyword
2.fill in letters of keyword (sans duplicates)
3.fill rest of matrix with other letters
Encrypting and Decrypting
-plaintext is encrypted two letters at a time
1. if a pair is a repeated letter, insert filler like X’
2. if both letters fall in the same row, replace each with letter to right (wrapping back to start from end)
3. if both letters fall in the same column, replace each with the letter below it (again wrapping to top from
bottom)
4. otherwise each letter is replaced by the letter in the same row and in the column of the other letter of the pair
C++ by Dissection presents a thorough introduction to the programming process by
carefully developing working programs to illuminate key features of the C++ programming
language. Program code is explained in an easy-to-follow, careful manner throughout.
The code has been tested on several platforms and is found on the bundled CDrom
accompanying this text. The code in C++ By Dissection can be used with most C++
systems, including those found in operating systems such as MacOS, MS-DOS, OS/2,
UNIX, and Windows.
The MINI2440 is an effecient ARM9 development board with a comprehensive price, it characterizes simple method and high performance-price ratio. Based on the Samsung S3C2440 microprocessor, it embodies professional stable CPU core power source chip and reset chip to ensure the stability of the system operation. The PCB on the MINI2440 board is designed to be 4-layers board, adopting the ENIG technology and professional equal-length wiring to ensure the completeness of the signals of the key signal wires and manufactured and released under stringent quality control plans. With the help of this detailed manual, users are supposed to become proficient in the development process of embedded Linux and WinCE operating system, they are supposed to get the foundation, so long as they have obtained the basic and necessary knowledge about the C language, in two weeks.
This paper presents an overview of mobile WiMAX technology
and discusses the key role of spectrum analysis for ensuring reliable
systems’ operation and deployment
A certification path is an ordered list of certificates starting with a certificate issued by the relying
party s trust root, and ending with the target certificate that needs to be validated. Certification
path validation procedures are based on the algorithm supplied in ITU-T Recommendation X.509
and further defined in Internet Engineering Task Force (IETF) Request for Comments (RFC)
3280. Certification path processing verifies the binding between the subject distinguished name
and/or subject alternative name and the subject public key defined in the target certificate. The
binding is limited by constraints, which are specified in the certificates that comprise the path,
and inputs that are specified by the relying party. To ensure secure interoperation of PKI-enabled
applications, the path validation must be done in accordance with the X.509 and RFC 3280
specifications. This document provides the test assertions and the test cases for testing path
validation software against these specifications.
