ALPHA-VISION® Versioning, Licencing and File Encryption: Encryption

Encryption

SUMMARY

Encryption functions for Runtime data.

CONTENTS

1. Affected File Types
2. Encryption Key
3. Encryption Levels

Affected File Types

When encryption is active, all files of type *.DO, *.DIS, *.CA and the *.zip-files created by AvZipArchives.exe are encrypted. It is not possible to select only certain files for encryption. To access archived data encrypted at Runtime by AvZipArchives.exe with the usual analysis tools they have first to be decrypted using AvZip2Dbf.exe.

Encryption Key

The encryption key is stored in the licence file VISION.LIC. The same VISION.LIC must be used for encrypting and decrypting the data. When an attempt is made to decrypt data with no key in the licence file or another key than the one used for encryption, an error message will be created.

• The encryption key has a maximum length of 80 characters
• The encryption key should have a minimum length of 16 characters

Encryption Levels

There are 2 nested encryption levels: when level 2 is active, level 1 is active also.

All affected files are compressed but not encrypted. File names are not changed.

When a encryption key is found in VISION.LIC, ALPHA-VISION^®-programs try to encrypt or decrypt the affected files using the key found. File names are not changed. If the wrong key is used for decryption the file access fails.

When a encryption key is found in VISION.LIC and a file VisionLic.xis is found, the affected files will be treated in the same way as in level 1. After encryption and before decryption however the Chiasmus-algorithm is used to encrypt or decrypt the file a second time. All affected files receive an additional extension of *.xia, so the final file name is

<original-file-name>.<original-extension>.xia

Example: MyProject.dis becomes MyProject.dis.xia