As a guide, the authorized access list should be restricted commensurate to the restrictions the organization places on root level server access. Access should be restricted to those individuals (plus necessary facility personnel) required to support the environmental and network infrastructure.
If the access control system is tied to the building's system, ensure there are controls in place to approve and authorize access list changes. This will negate building security administrators simply granting access because someone asks for access.
Standalone or independent systems give you more control, but add to the complexities of tasks on a usually already overburdened IT staff. However, some audit standards mandate this level of control.
Additionally, it would be worthwhile checking with the audit team to ensure their requirements are addressed in the design process. That will eliminate your discovery of something post-construction that you should have included.
ABOUT THE AUTHOR: JP Callahan is a former counter-intelligence agent with the U.S. Department of Defense and currently runs data center security for Verizon Business, the company's data center hosting arm.
This was first published in January 2007