Cryptx File Security System
Version 1.0
Manual Updated: Thursday, October 23, 1997


Table of Contents

1) 	Overview of File Security and Encryption
2) 	How to Encrypt a File on your computer
3) 	How to Decrypt ("Unlock") a file previously encrypted by Cryptx
4) 	A Note about Passwords
5) 	Pricing and Updates
6) 	Technical Notes about the Encryption Engine
7) 	Contacting PBD Technologies



Section 1: Overview of File Security and Encryption

Encryption is defined as a method in which data or text is encoded so that unauthorized individuals are not able to access it.  With the increasing necessity of  business and personal communications via public channels, ie, telephones, internet, etc.,  cases of data theft,  invasion of privacy , and cooperate espionage are also becoming alarmingly common.

Although secure encryption systems have been available for many years now, their prohibitive  cost has effectively kept sophisticated binary encryption techniques in the hands of governments  and major corporations. However, with new breakthroughs in personal PC processing power, it is
now possible for small businesses and individuals to have access to the same encryption power that has been test and certified by the US government  for use in it's communications.

The DES Engine

The Cryptx File Security System utilzes an encryption engine based up the  Data Encryption Standard (DES) , an encryption block cipher first defined and endorsed by the U.S. government in 1977 as an official standard. The encryption "workhorse" of the banking and financial communities for over twenty years, DES has been renewed every five years by the National Institute of Standards and Technology (NIST) and is presently up for review. DES has been extensively studied since its publication and is the most well-known and widely used secret-key cipher in the world.


How it Works

When designing and coding the encryption engine, our primary consideration was ease of use and speed of encryption.  By minimizing esoteric options and settings from the interface, we believe we have created an encryption engine even the most casual computer user can quickly  implement.

When a file is encrypted using this program, CFFS specifies a cryptographic algorithm that converts plaintext to ciphertext using a user supplied key, a process called encryption.  The same algorithm is used with the same key  to convert ciphertext back to plaintext, a process  called decryption.  The DES consists of 16 "rounds" of operations that mix the data and key  together is a prescribed manner using the fundamental operations of permutation and substitution. This process will completely scramble the data and key so that every bit of the ciphertext depends on every bit of the data and every bit of the key (a 56-bit quantity for the  DES).  After sufficient "rounds" with a good algorithm, there should be no correlation between the ciphertext and either the original data or key - in other words, the encrypted data is completely secure.
 
.Section 2 :  How to Encrypt a File on Your Computer

Encrypting a file on your computer using CFSS is simple, fast, and completely secure. 

Step 1:  

From the main screen, select the file that is to be encrypted, using the Browse button if neccesary.  The filename should contain the complete path to the file, such as:

c:\mydocuments\mydata.doc

or

c:\windows\picture1.jpg

Step 2:

Select the Output File Name. This is name of the new file created when CFSS begins the  encryption process.

To prevent accidental data loss, we have designed this system to not specifically overwrite a particular file unless the user specifically instructs CFSS to do so. Rather, it will create a new file from the original data.

Users should also specify the complete path into  which the new  encrypted file should be placed.  If no path is specified, the new file will be placed in the directory specified in Step 1.

Step 3:

Select Password / Key.  For all practical purposes, it is impossible to decode a file encrypted with CFSS without the original key. Care, therefore, should be taken in selecting and storing your passwords! 

For maximum security, select a 'non word', or a grouping of text and numbers. 

Remember that if you intend to have someone decrypt your file, they must also be in possession of your key.

Section 3:  How to Decrypt a File on Your Computer

You can quickly and easily decrypt any file encrypted by CFSS or any other DES engine by selecting the "Decrypt..." option from the main screen, which opens the "Decrypt" screen.

To begin, just reverse the steps in Section 2.  Select the encrypted file, an output file name, and password.   If your password is correct, your new file will contain the unencrypted data.

Note: Files or data encrypted by CFSS cannot be decrypted without the original password. If you forget or loose your password, your data is, for all practical purposes,  lost.


Section 4: A Note about Passwords

If a password is easily guessed, or is delivered with the encrypted file, the whole point of encrypting data is lost. To ensure maximum security for your files and documents, it  is advisable to use non standard combinations of letters and numbers, rather than whole words.


Section 5: Pricing and Updates

Because encryption is a rapidly changing technology, both from a technical and legislative perspective, we intend to support this product with regular improvements and upgrades for the life the software. Updates are available free of charge to all registered users.

Section 6: Technical Notes about the Encryption Engine

CFSS utilizes the 56 Bit DES ("Data Encryption Standard") algorithm for its encryption functions.

Originally created  as Federal Information Processing Standard Publication (FIPS PUB) 46 in 1977 by IBM, the DES was obtained by NIST (then the National Bureau of Standards) to provide a secure system for the protection of the confidentiality and integrity of the federal government's sensitive computer information. DES has been approved as  American National Standard X3.92-1981/R1987.  

Security Provided by DES 
 
The security provided by the DES depends on several factors:  mathematical soundness, length of key, key management, input data formatting, mode of operation, implementation, application and threat.   
 
The DES was developed to protect computer data in  federal computer systems against a number of passive and active attacks in communications and storage systems.  It was assumed that a knowledgeable person might seek to comprise the security system with resources commensurate to the value of the information to be obtained.  Applications included Electronic Funds Transfer, privacy protection of personal information, personal authentication, password protection, access control, etc.   
 
Section 7: Contacting Us:

Feel free to contact us with any questions you may have, or if
you would like to order one of our products.

PBD Technologies
13502-H Whittier Blvd  
Suite 304
Whittier, CA 90605

(503) 	235-9442
(503) 235-9254

http://www.cryptx.com

sales@cryptx.com
support@cryptx.com



