project, security A project which grew out of the ARPA

support for Multics and the sale of Multics systems to the

US Air Force. The USAF wanted a system that could be used to

handle more than one security classification of data at a

time. They contracted with Honeywell and MITRECorporation to figure out how to do this. Project Guardian

led to the creation of the Access Isolation Mechanism, the

forerunner of the B2 labeling and star property support in

Multics. The DoD Orange Book was influenced by the

experience in building secure systems gained in Project

Guardian.