ACC: How Microsoft Access Uses Encryption

Last reviewed: April 3, 1997
Article ID: Q140406
The information in this article applies to:
  • Microsoft Access versions 1.0, 1.1, 2.0, 7.0

SUMMARY

Advanced: Requires expert coding, interoperability, and multi-user skills.

This article discusses how encryption is used in Microsoft Access.

MORE INFORMATION

Encryption enables you to prevent anyone from using a utility program or word processor to read and write data in a Microsoft Access database (.mdb) file. This feature is different from Microsoft Access security (which sets user and group permissions on database objects); its sole purpose is to make a database indecipherable by a file or disk editor.

Microsoft Access uses an RC4 encryption algorithm with a 32-bit key from RSA Data Security Incorporated. If you are creating an international application, this algorithm is acceptable for export outside of the United States (according United States export laws) because the key is less than 40-bits.

When you encrypt a database, all objects (tables, forms, queries, indexes, and so on) are affected because encryption is implemented at the page- level and not at the data-level. Microsoft Access encrypts a database in 2K (kilobyte) pages, regardless of the data stored in a page. Each encrypted page is assigned a unique 32-bit key.


Keywords : GnlEncr kbusage
Version : 1.0 1.1 2.0 7.0
Platform : WINDOWS
Hardware : X86
Issue type : kbinfo


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Last reviewed: April 3, 1997
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