View source for Compartmentalization (information security)

{{Short description|Limiting access to information on a need-to-know basis}}
'''Compartmentalization''', in [[information security]], whether public or private, is the limiting of [[access to information]] to persons or other entities on a [[need-to-know]] basis to perform certain tasks.

It originated in the handling of [[classified information]] in [[military]] and [[intelligence (information gathering)|intelligence]] applications. It dates back to [[Classical antiquity|antiquity]], and was successfully used to keep the secret of [[Greek fire]].{{sfn|Roland|1992|pp=663–664}}

The basis for compartmentalization is the idea that, if fewer people know the details of a mission or task, the risk or likelihood that such information will be compromised or fall into the hands of the opposition is decreased. Hence, varying levels of clearance within organizations exist. Yet, even if someone has the highest clearance, certain "compartmentalized" information, identified by [[code name|codeword]]s referring to particular types of secret information, may still be restricted to certain operators, even with a lower overall security clearance. Information marked this way is said to be '''codeword–classified'''. One famous example of this was the [[Ultra (cryptography)|Ultra]] secret, where documents were marked "Top Secret Ultra": "Top Secret" marked its security level, and the "Ultra" keyword further restricted its readership to only those cleared to read "Ultra" documents.<ref>{{cite web|url=http://www.cl.cam.ac.uk/~rja14/Papers/SE-08.pdf|title=Security Engineering: A Guide to Building Dependable Distributed Systems, First Edition, Chapter 8.2: Compartmentation, the Chinese Wall, and the BMA Model|author=Ross Anderson|page=161}}</ref>

Compartmentalization is now also used in commercial [[security engineering]] as a technique to protect information such as [[medical record]]s.

==Example==
{{no sources section|date=October 2024}}
An example of compartmentalization was the [[Manhattan Project]]. Personnel at [[Oak Ridge, Tennessee|Oak Ridge]] constructed and operated [[gas centrifuge|centrifuges]] to isolate [[uranium-235]] from naturally occurring uranium, but most did not know exactly what they were doing. Those that knew did not know why they were doing it. Parts of the weapon were separately designed by teams who did not know how the parts interacted.{{cn|date=October 2024}}

==See also==
* [[Information sensitivity]]
* [[Principle of least privilege]]
* [[Sensitive compartmented information]]

==References==
{{reflist}}
{{refbegin}}
* {{citation
 | last=Roland
 | first=Alex
 | title=Secrecy, Technology, and War: Greek Fire and the Defense of Byzantium, Technology and Culture
 | jstor=3106585
 | journal=Technology and Culture
 | volume=33
 | issue=4
 | year=1992
 | pages=655–679
 | doi=10.2307/3106585
}}
{{refend}}

[[Category:Data security]]
[[Category:National security]]
[[Category:Classified information]]
[[Category:Intelligence assessment]]