The Common Data Security Architecture (CDSA) is a multiplatform,industry-standard security infrastructure. Starting with Version7.3-1, HP provides CDSA as part of the OpenVMS Alpha operating system.CDSA is compatible with OpenVMS Alpha Version 7.2-2 and higher.
CDSA provides a stable, standards-based programming interfacethat enables applications to access operating system security services.With CDSA, you can create cross-platform, security-enabled applications. Securityservices, such as cryptography and other public key operations,are available through a dynamically extensible interface to a setof add-in modules. These modules can be supplemented or changedas business needs and technologies evolve.
CDSA is security middleware that provides flexible mix-and-matchsolutions across a variety of applications and security services.CDSA insulates you from the issues of incorporating security intoapplications, freeing you to focus on the applications themselves.The security underpinnings are transparent to the user.
CDSA was originally developed by Intel® ArchitectureLabs and was released to the OpenSource community in May 2000. HP'sCDSA implementation is based on the Intel V2.0 Release 3 referenceplatform, which implements CDSA V2.0 with Corrigenda, as definedin The Open Group's Technical Standard C914, May 2000.
HP Open Source Security for OpenVMS Volume 1:... 
Introduction to CDSA