While holding PatchGuard - the Kernel Patch Protection technology in 64-bit Windows Vista - in place, Microsoft announced the release of a draft Application Programming Interfaces together with a Criteria Evaluation document, enabling independent security developers to access the operating system's core.

The Criteria Evaluation document was released to detail Microsoft criteria of evaluation in respect to partner requirements for the Windows Vista Application Programming Interfaces. The APIs made available are in fact a draft version designed for testing, with the final version scheduled for release simultaneously with Vista Service Pack 1.

Microsoft released a total of four classes of APIs focused on the building and execution of processes and threads, on third-party security products protection, on memory control and on actions related to image loadings.

The Redmond Company explained that the draft APIs have been constructed in collaboration with the security developers and that the company will continue to look for partner feedback by the end of January 2007. Microsoft expects little change to be introduced to the draft APIs, and in this context, the final set of APIs will differ little from the draft version.

According to Microsoft, all the requirements of the independent security software developers have already been met with the draft set of APIs, but the Redmond Company will collaborate with security partners in order to deliver additional Application Programming Interfaces if that will be the case.

Moreover, Microsoft made it clear that the set of Application Programming Interfaces will not offer third-party security developers the same kernel access as is the case of 32-bit versions of Windows. The documented APIs will merely enable the extension of 64-bit Vista kernel functionality.