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S U P E R C R Y P T Version 3.xx Reference Manual Encryption, decryption, and cryptanalysis program. Supporting the secure Data Encryption Standard (DES). Context sensitive help and on-line manual make it easy! Super Crypt is user supported software (Shareware). If you use it past the initial 15 day evaluation period you are required to register it. No exceptions! Super Crypt "Encryption/Decryption/Cryptanalysis -- Fast, Safe, and Easy to Use" is published by Super Software 403 East NASA Rd 1, Suite 377 Webster, TX 77598 U.S.A. Voice: (713) 488-0210 FAX: (713) 280-0525 Published and printed in the United States of America. Copyright 1990 Super Software as a licensed, unpublished, proprietary work. All international rights reserved. 1 The printed Reference Manual and associated registered software may not be copied, resold, reproduced, disclosed, archived, transmitted, or transferred in any form, electronic or otherwise, without the expressed written permission of Super Software. You may freely distribute the Shareware version. Super Software hereby grants a "book" license to the original individual (even if purchased by a company) user of this copy of Super Crypt. You may use the program on your computer and make one backup for storage as long as there is no possibility of use or residence on more than one machine at any time. Just like two people cannot read the same book in different locations at the same time. Every registered copy of Super Crypt has a unique embedded serial number for traceabililty. You may not sell or give copies of the registered program or printed documentation to anyone. No exceptions. Pricing, specifications, and conditions are subject to change without notice. Send all registrations and inquires for site (multiple CPU or network) licensing to Super Software at the above address. Disclaimer: Super Software, Inc. makes NO claims AND offers NO warranties of any sort with Super Crypt. Super Software assumes NO responsibility for any sort of damage resulting from the apparent or actual use of Super Crypt (mental or physical). The program provided is not guaranteed as to merchantability or fitness for its ultimate use. The user accepts all responsibility for use and may not resell the program. IBM PC/XT/AT are registered trademarks of the International Business Machines Corporation. Super Crypt is a trademark of Super Software. Other trademarks belong to their respective owners. 2 PREFACE This manual is dedicated to Mae and Dave of MaeDae Enterprises without whose never ending perseverance, Super Crypt would not be possible. ABOUT THIS MANUAL You will notice that this manual is concise. This is intentional as we have strived to make Super Crypt the easiest program of its type to use. We have opted to provide an on-line manual and extensive context sensitive user help. Feel free to use this reference manual to install and get acquainted with the program. For many of you, this may be your first exposure to Shareware. To help eliminate possible confusion, we have included a short description of the Shareware marketing concept, explaining what it is and why it relies on you for its survival. What is Shareware? Shareware is not a kind of software. It is a revolutionary method of marketing Commercial software. Our software is Commercial software that we are allowing you to examine for 15 days before you make the purchase decision. With traditional marketing methods, you have to purchase Commercial software from a computer store or through mail order businesses, then try it out, and hope it does what you want. Shareware allows you to "try before you buy!" We rely upon you, the customer, to examine our software. If you find our software useful, please register. Your support is needed for us to continue to improve our products. Enough of this verbage. The real fun and learning begin when you use the program. So enjoy, live long, and prosper. With warmest regards, The gang at Super Software. 3 Table of Contents ================= Page Description ==== ============ 5. What is the Data Encryption Standard (DES)? 5. What is Super Crypt? An overview of its features. 6. Hardware Requirements 7. Installation - Introduction 7. Installation for the Shareware Diskette 8. Installation for Floppy Disk Drive Systems 8. Installation for Hard Drive Systems 11. Getting Started 12. Tutorial 14. Additional Features 15. Troubleshooting 17. Basic Definitions 18. Encrypted Ramblings 4 WHAT IS THE DATA ENCRYPTION STANDARD (DES)? =========================================== Most encryption schemes are kept secret. One exception is the Data Encryption Standard (DES) which was issued by the U.S. National Bureau of Standards. Even the National Security Agency (NSA) was intimately involved in the development and acceptance testing of the algorithm. Now we know where DES came from, but how does it work? DES performs its encryption by working on a block of 64 bits of your data using a 64 bit key (we generate the 64 bit key from yours). Basically DES is a substitution cipher. We know this sounds very technical but don't worry, we have hidden all the complexity of DES behind an extremely easy to use interface. Our context sensitive help and extensive on-line manual makes protecting your data a simple task. Why did we choose to implement DES? We chose DES because it is a standard. Its ability to protect your data is well documented. Our goal is to provide you the best possible software tool for the protection of your data. We use multiple layers of encryption with DES as the final layer of protection for your data. Because of this approach, we feel your data is protected far better than using DES by itself. WHAT IS Super CRYPT? ==================== Super Crypt is a powerful encryption/decryption package that allows you to: 1. Encrypt any file using Data Encryption Standard encryption, 2. Decrypt the file using a confidental key, 3. Perform encryption and decryption on entire groups of files in a batch mode, 4. Obtain file statistics (frequency/distribution, mode, mean, median, and more) to determine how well the file is encrypted (also to look at other encrypted files), 5. And do it all without cryptic commands! 6. Other features: -- Keyboard macros - 100+ macros each with 1000 keystrokes. -- DOS Shell - Call up a DOS shell at any prompt. -- Screen Blanker - Also protects your key by erasing it! Super Crypt comes configured to work with most display adapters and monitors. You can easily customize it to suit your needs. 5 HARDWARE REQUIREMENTS ===================== 1. IBM PC/XT/AT, IBM PS/2, or fully compatible computer. 2. 512K RAM and DOS 3.0 or later. 3. Any monitor. Super Crypt has been written to accommodate monochrome, color, enhanced graphics, and video graphics array adapters. Some "autoswitch" adapters may need to be in "manual". 4. At least one 5.25" floppy disk drive. Two floppy disk drives or one floppy and a hard disk (300K free space minimum for the full system) are strongly recommended. 6 INSTALLATION - INTRODUCTION Always run and read the README.EXE =========================== file for the latest info. Two 5.25" diskettes are normally included with Super Crypt. Also, some copies sold thru various distributors may vary in disk quantity and make up, but all the files will be there. The diskette with the bright green label contains a Shareware version of Super Crypt that has additional information screens, but all features are enabled. The purpose of this diskette is to check your entire system for proper operation before you break the seal on the full system diskettes. (a.k.a. Diskette #0) Diskette #1 (the main disk) contains the actual program, the context sensitive help, the on-line manual, and additional support files. Diskette 1 is sealed. INSTALLATION FOR THE SHAREWARE DISKETTE Always run and read the ======================================= README.EXE file for info. 1. Make sure the Disk Operating System (DOS) has been loaded into your system and you are at A>> (system prompt). If you are confused, consult your computer manual or your local PC "guru" first as we can only help you with Super Crypt. If you need help with DOS, try a local community college, adult continuing education course at a local high school, or a "Puter-Tutor" type training service. 2. Insert the Shareware diskette into DRIVE A. 3. Type SC and press RETURN (ENTER on some machines, also, <<cr>> ) The opening screen of Super Crypt will ask you to press any key to continue. Pressing any key will allow you to scroll through various opening screens with important information (these screens may not be included). When the Super Crypt's Main Menu appears on your screen, go to the "GETTING STARTED" section of the manual (this section is just after this installation section). Follow the easy to understand instructions and welcome to the world of Super Crypt! Some packaging may not contain the Shareware diskette, so just ignore this section of the manual if you do not have one. Reasons include site licensing and/or other distributor arrangements. P.S. The Shareware version of Super Crypt will do everything the registered version will do. However, it suitable for only a 15 day trial period, after which you are expect to regi$ter. 7 Feel free to share ONLY the Shareware version with friends and potential users of Super Crypt for evaluation purposes only. You may not use the Shareware version on other machines in order to avoid purchasing additional copies of the full program. You may not give away any copies or make more than one copy of the fully operational program for other than archival purposes. The full version of Super Crypt has a unique serial number embedded in each copy for traceability. INSTALLATION FOR FLOPPY DRIVE SYSTEMS (NO HARD DRIVE) ===================================================== Always run and read the README.EXE file for the latest info. Please read through the entire installation procedure before proceeding. This may save you some frustration later. 1. Make sure the Disk Operating System (DOS) has been loaded into your system and you are at A:> system prompt. If you need help, consult your DOS manual or find a local computer "guru" to help you out. 2. Make a backup copy of the diskettes. ONLY operate from backup copies! 3. Insert diskette #1 into DRIVE A and type SC followed by Return. No additional steps are needed. Please sign and mail your registration card to the address on it. Make a copy for your own records. User support and updates cannot be provided UNTIL your registration form is on file. Although Super Crypt is not copy protected, you may make copies for archive purposes only. The purchase of one copy does not authorize you to install Super Crypt on more than one machine or on a network. If you intend to install to a hard drive, but run the program from your floppy drive first, delete the file SC.CNF (if it exists) before loading to your hard drive. INSTALLATION FOR HARD DISK SYSTEMS Always run and read README.EXE ================================== for the latest information. 1. Make sure DOS has been loaded into your system and you are at C:>. (Note: Installation on a hard disk will require a minimum of 300K of free disk space for the full system.) 2. Create a subdirectory called "SC". If you are not familiar with creating a subdirectory, simply type MD C:\SC followed by Return If your drive is other than C:, substitute the appropriate letter. 8 3. Place diskette #1 (bright red label) into DRIVE A and type COPY A:*.* C:\SC followed by Return The program, on-line manual, and other related files on diskette #1 will now be copied to your hard disk. 8. At C:> type CD \SC followed by Return This will put you in the SC subdirectory. 9. Type SC followed by Return. Admire the glittering opening screen, press any key to continue, and select one of the menu options on your screen. IMPORTANT INSTALLATION NOTES: 1. Diskette #1 contains many files in addition to SC.EXE. Because Super Crypt is a large program, the additional files SC_HM.TXT and SC_HM.INX are required for context sensitive help and on-line manual. So please make sure that these files are in your default directory when running the program. If you have only one floppy drive, you can build a work diskette containing: SC.EXE, SC_HM.TXT, and SC_HM.INX. Do not copy SC.CNF, if it exists. A new SC.CNF will be saved when you select options and retain them. 2. If your Super Crypt does not run properly: A. Delete the SC.CNF file and try to run again. Check out our troubleshooting section near the end of this manual. B. Your machine may not be totally IBM PC operating system compatible. This is not always disastrous and a quick call to our phone support staff may solve your problem. C. You may have a slightly incompatible "EGA" card with auto switch features. Usually, turning off autoswitch and forcing the system into the EGA mode solves the problem. D. If you have any memory resident programs or system drivers, try running without them loaded in your computer. On some computers, ANSI.SYS is suspect. 9 3. If your monitor appears to be losing certain characters or features, you may have a "color" system with a composite monochrome (green, amber, LCD, etc.) monitor. Adjust the contrast and brightness of the monitor until the screen is readable. In some cases, you may have to go to the Install Menu to choose acceptable "colors". See the "Troubleshooting" section. 4. This Manual is designed to give you a general overview and familiarity with the program. More complete, up-to-date information is available to you through the context sensitive help (F1) and the on-line manual. When using the more advanced features of the program, the help screens will guide you through the toughest questions with ease. As Super Crypt continues to add more features, you can be sure that the on-line manual and context sensitive help will give you the guidance needed. This way everybody wins. We don't spend money continually revising manuals and charging you higher prices, and you get what you want and deserve: accurate up-to-date information. So fire up the computer, dig in, and welcome to Super Crypt! 5. Note to advanced users: To be able to run Super Crypt from any point on your hard disk, create a batch file called SC.BAT and store it in your path. It should contain --> C:\SC\SC.EXE /C=C:\SC\SC.CNF This will enable you to run Super Crypt from anywhere on your hard disk with full context sensitive help and on-line manual. Be sure to install the help/manual path within Super Crypt to be C:\SC. Super Crypt supports optional configuration files through the use of the /C= command line switch. You saw an example of this in the above section. Create as many unique configuration files as you would like using unique names. At startup time you can specify any of the configuration files through the use of an optional /C=MyConfig.CNF type command. 10 GETTING STARTED =============== After you type SC <<cr>> (Enter or Return), the opening screen of Super Crypt will appear. At the bottom of your Super Crypt opening screen you are instructed to press any key to continue. The MAIN MENU will appear on your screen. The Main Menu options with descriptions are below. On-Line Manual: This is an on-line manual covering features of Super Crypt in more depth than the documentation available in this manual. Encrypt: Encode or hide the information within a file to make it unreadable to anyone who doesn't have a special access code called a key. Just like you can't unlock a lock without a key, you can't look at an encrypted file without the key. You limit the number of people who know the key, thereby limiting the number of people who can access the intelligence within the file even if they have access to the file. A key is simply a combination of letters and numbers. They may or may not have any conventional meaning. For example, the letters xyz12345 could be a key. Please note that we provide two methods of encryption and decryption. The methods are our lighter proprietary method and the Data Encryption Standard (DES) encryption method. The DES provides the more powerful method, but is much slower. Choose the appropriate method for the level of protection you require. Super Crypt can't retrieve the key you used to encrypt the file. If you forget the key for the decryption process you can also forget your file. This is the nature of data protection. We have no way of helping you recover any lost data due to you losing the key! So be careful! Decrypt: Decryption is the opposite of encryption. You use a key with the encrypted file to reverse the encryption process giving you the file you started with. Analysis/Statistics: Here you can "look" at any file to see how the characters are distributed within the file. Statistics are provided to allow you to get a feel for the "goodness" of the encryption process. Install: The installation portion of Super Crypt allows you to customize the colors, directory defaults, and other options. Quit and exit to DOS: All good things must come to an end. Choose this option if you want to leave Super Crypt and return to DOS. You may choose any of the displayed options by pressing the first letter or by moving the light bar (the giant cursor) with your cursor keys or space bar to the desired option and pressing 11 Return. Please note that once you have a pulldown active, the first letter selects options within the pulldown NOT the top Super Crypt main menu line. (If you have a "color" system with a composite monochrome monitor and don't see a light bar or other features, try adjusting the brightness or contrast of your monitor. You may also need to install special colors for your system. See the Install Menu.) Now let's do something simple to demonstrate how Super Crypt works. Press E (Encrypt) Then press enter with the "pick from a menu" option highlighted. You will be asked for the directory mask and path for your files. Your screen should clear and you will be given a list of files to encrypt. Press enter with the first file highlighted. Press enter again on the next menu to accept the default name for the encrypted file. Don't forget to pick a unique key for encrypting the file. You have just encrypted your first file. *** Warning *** Super Crypt remembers the last key you used! You don't have to retype it in if you want to use the same key for the next operation. This makes it easier for you but it can lead to a problem if you walk away from your computer with Super Crypt still running. Another user could potentially find out the last key you used by checking the encrypt or decrypt screens. As a matter of standard policy, you should NEVER encrypt or decrypt a file and then leave the area with Super Crypt running. TUTORIAL (ENCRYPTING/DECRYPTING A FILE) ======================================= Now let's encrypt a file while using various options. Don't worry about being fancy or being intimidated; this first use is only for practice. We can get fancy later. From the Main Menu, highlight the encrypt section and press E (Encrypt) a file. The encrypt pulldown will appear on the menu with the SelectMenu option highlighted. Steps are: 1. Press enter. You will now be prompted for where the file is located which is to be encrypted and the mask for the directory. You are being asked for the subdirectory name for its storage location. 12 2. Press enter to accept the default directory. A directory of files will appear with the first filename highlighted. 3. Press enter to use this file. You will then see a window listing multiple options for paths, key, and output file. Since this is the first file we've encrypted, the key won't contain anything. The cursor should be on the line prompting you for a key. So choose an easy to remember key and type it in. Accept all the defaults by pressing enter. Note: Pressing enter on the destination filename is the signal that you are done editing the options. 4. A file will now be written in encrypted form using the default key and the default filename show. The file to be encrypted is broken into small blocks which can be easily be read into your computer's memory then encrypted. You will see the block number increase as each block is processed. The screen will display an "Operation Successful" message and return to the main menu after it finishes. From the Main Menu, highlight the decrypt section and press D (Decrypt) a file. To decrypt a file you reverse the process for encrypting a file. You first select the file you just encrypted using the same steps as for encryption. Use the same key as when you encrypted the file. The output file name will be extracted from the header of the encrypted file. It's that simple. 13 ADDITIONAL FEATURES =================== MULTIPLE FILE OPERATIONS Use the tag option to tag multiple files for encryption or decryption in a batch mode. When you use the directory screen you have the option of tagging multiple files. If multiple files are tagged, Super Crypt will prompt you for some information and then work with the entire group of files at one time. AUTO FILENAME GENERATION Super Crypt will automatically generate a unique destination name when you encrypt a file. You have the option to override this feature for single file operations. We suggest a tilde (~) as the first character of an encrypted file's extension. We automatically generate an extension of a ~ followed by two characters. Your directory is checked for files and we generate 00-99 and AA-ZZ until we find a unique unused filename. Most of the time the extension will be a .~00 for the first encrypted file, a .~01 for the second, etc. This technique is what allows us to encrypt entire groups of files in a batch mode without your manual inputs. Using this method we can generate about 776 unique filenames by working with the file extension and leaving the main portion of the filename unchanged. DOS SHELL Super Crypt provides a quick interface to DOS for you. At any prompt press Ctrl+X (control X). A second copy of the DOS command processor will be loaded to allow you to use standard DOS commands. Type EXIT and press enter when you want to return. Warning: Do NOT load any memory resident programs while in the DOS shell! KEYBOARD MACROS Keyboard macros are supported to allow you to easily emulate you at the keyboard. They allow you to attach command strings to over 100 keys. These execute exactly as if you were at the keyboard typing the commands. We support Shift+F1-F10 directly as a single keystroke. We also have two keystroke macros where the first key is Ctrl+O then you press a second key. For the two keystroke macros first press Ctrl+O then 0-9, Alt0-9, A-Z, AltA-Z, AltF1-F10, or CtrlF1-F10. When you play back the macros, the Shift+F1 through Shift+F10 keys execute directly, all others are two keystroke combinations where you first use Control+O as the first key. The shifted F10 is the autostart macro and will execute automatically when you bring up Super Crypt. To modify the keyboard macros use the Alt+= key combination (hold down Alt and tap =) to call up the macro menu. We provide extensive context sensitive help in the program to make this easy. 14 The default keyboard macro file's name is SC.MAC. If you would like to specify a different name use the /M=MyMacro.MAC command line argument at startup time. Example: SC /M=C:\SC\MyMacros.MAC (The path is optional) SCREEN BLANKER Super Crypt will automatically blank your screen after a few minutes of inactivity. This will prevent your screen from having a pattern burned into its phosphor if you leave Super Crypt running for extended periods of time in an unattended mode. A special feature of the screen blanker is to zero out the stored key. If you leave your computer unattended long enough for this screen to come up, the key that you last used has a chance of being compromised. This automatic key erase feature of Super Crypt will help protect your data by automatically erasing your key from memory. COLOR CONTROL For users with color monitors, the color option in the Install menu gives you total color control of text, background, borders, highlighted areas, etc. Just press C from the install menu. TROUBLESHOOTING =============== Displays If, after loading Super Crypt, you see text and no borders, or nothing at all, you may have a compatibility problem. Super Crypt high speed screen updates which may cause a problem with some not-too-close IBM PC operating system compatibles. For example, the Tandy 2000 and Sanyo 555 series computers are not compatible with Super Crypt. IBM type monochrome (MDA), color (CGA), EGA (enhanced graphic), and VGA (video graphics array) adapters are known to work with Super Crypt. If you are using a compatible color video card with a green or amber screen, or LCD monitor, you may need to adjust your brightness and contrast, or Install other "colors" from the color installation screen. Also see the BWVIDEO.DOC file. BWVIDEO.COM is a "color killer" that works especially well with composite monochrome monitors, and lap top computers with LCD monitors. Sometimes executing the DOS "MODE BW80" command works. Some "autoswitch" Enhanced Graphic Adapters and "Hercules" type mono-graphics cards may need to have their auto modes disabled for proper operation. If Super Crypt will not run, you may have insufficient memory, or too many memory resident programs. Try running Super Crypt 15 with no memory resident programs. If Super Crypt just stops running or "freezes", you may have removed the program diskette from the disk drive. The program disk must be available to access the context sensitive help and on-line manual. Of course, if SC.EXE and its support files are on your hard drive, this will probably not be a problem. Occasionally, certain memory resident, TSR, or "pop-up" programs conflict with Super Crypt. In general, there is no problem, but there are many new programs being written without regard to the system requirements of Super Crypt. Remove them from memory, and try again. If that fails, try getting rid of device drivers in your CONFIG.SYS file. ANSI.SYS is a prime suspect for some not-so-compatibles. The latest information on monitors and displays may be put on a distribution diskette (see Disk #1) in a file called MONITORS.DOC. To print this information on your printer, just make sure the file is in the default directory and type COPY MONITORS.DOC PRN <<cr>>. MISCELLANEOUS Super Crypt works closely with your computer's hardware to gain much of its speed. However, it never directly addresses the hardware without using standard DOS calls. If you have any memory resident software that modifies the way DOS works, then Super Crypt may not function properly. We strongly recommend that you remove all memory resident software before running Super Crypt! 16 BASIC DEFINITIONS: ================== The terms used in Super Crypt may be a little confusing. These terms are not made up, they are frequently used when discussing cryptography. We have tried to pick a handful of the most important terms and define them for you. They are: Data Encryption Standard (DES) - The Data Encryption Standard was issued by the U.S. National Bureau of Standards. The National Security Agency (NSA) was intimately involved in the development and acceptance testing of the algorithm. DES performs its encryption by working on a block of 64 bits of your data using a 64 bit key (we generate the 64 bit key from yours). Basically DES is a substitution cipher. Cryptography -- The general study of hiding the meaning of messages and the general techniques used for the hiding. Cryptanalysis -- The solving or breaking of codes without any knowledge of the key. Cipher -- Any technique, method, or scheme (substitution, transposition, and XOR) used to encrypt and decrypt text, without regard to its linguist structure. Plaintext -- The unencrypted or totally decrypted readable text. Ciphertext -- The unintelligible text, after encrypting it. Encrypting -- The process of encoding/encrypting a plaintext file to hide the intelligence. Decrypting -- Decoding an encrypted/ciphertext file. Key -- The text that was used to encrypt or decrypt a file. Sometimes called a code word. Keys can be simple everyday words or very complex combinations of characters that have no meaning. Some electronic information services pick your password by combining two regular words with a character between them. Examples keys: abc1234, Never:Again, and alsdkfqiaef. 17 ENCRYPTED RAMBLINGS - SOME GOOD INFORMATION =========================================== As networks proliferate the need for data security increases. The world in the past has largely depended on physical security, that is safes and locks. Computers, much to the bureaucrats consternation, are rapidly eroding the possibility of physical security (wherever a modem is connected to a phone line). Laws will be passed, but in the final result, honesty depends on good locks and all the ministrations of legislators and bureaucrats will come have little positive effect on security. Human nature will win out. The easier it is to get, the more likely it is to be stolen. Encryption provides part of the answer to the need for increased security. It will be especially useful in systems that are open to all users but have some confidential data. Instead of complex levels of users verification through passwords, everyone can get the file but only the people with the key can decode the information. Encryption at its present state is cumbersome and time consuming but, faster computers and better programs can ease this problem. This is where Super Crypt comes to the rescue. Encryption if nothing else is a fascinating exercise. Super Crypt implements a version of Vernham's machine developed at Bell labs in the 20's as part of its lite encryption methods. The original machine used Baudot code on the Teletype and performed an exclusive or (XOR) on each character of the message and the key to produce the encrypted character. The message was decoded by the same machine in the same manner. The method is considered unbreakable if two conditions are met. First the key is longer than the message and second the key is only used once, sometimes called a "one time pad." Typically the files you will be encrypting are much longer than the key (also much longer than the one we build from your key) thereby weakening the encryption. Distribution and maintenance of keys is unworkable in the day to day operation of any communications operation of any size. Super Crypt builds a much more complex key in its lite encryption from your simple key, in an effort to provide a method to ease this problem. It creates a one time pad based on your unique key. Most random keys are not truly random since all random functions are repeatable and their true randomness is somewhat suspect. What is the solution? Always the specter of a bigger and faster computers loom in the future to provide even faster encryption. Thinkers build on the best thoughts of those preceding them. More powerful computers and better encryption techniques will eventually provide a good solution to this problem. Super Crypt provides encryption methods that range from the fairly secure to the very secure. When you choose DES we use the lite encryption methods as the first layer followed by the secure DES. This further complicates the process of breaking the code. The best encryption in the world won't protect your data if you 18 give away the key. The secure encrypting of the data is our job. The choice of a good key and its protection is your job. How do you select a good key? Several things should be considered. The key should not have a lot of repeating characters, if they have any pattern to the eye they should not be used. The keys should be kept secure. Super Crypt supports keys up to 40 characters in length. We recommend you use as long a key as practical. Phrases or short sentences should work well as the key and still be easy to remember. NOTE: If there is any question of the randomness of the encrypted file, Super Crypt could be used on it multiple times using different keys. The true randomness of the key should not matter since the use of more than one key should make unraveling very difficult if not impossible. This process could be repeated until the paranoia of the person generating the keys was satisfied. 19