Editing Bell–LaPadula model (section)

{{Short description|State machine model used for enforcing access control in government and military applications}}

The '''Bell&ndash;LaPadula model''' ('''BLP''') is a [[Finite-state machine|state-machine]] model used for enforcing [[access control]] in government and military applications.<ref name=":0">{{cite book|last=Hansche|first=Susan|author2=John Berti|author3=Chris Hare|title=Official (ISC)2 Guide to the CISSP Exam|publisher=CRC Press|year=2003|pages=[https://archive.org/details/officialiscguide0000hans/page/104 104]|isbn=978-0-8493-1707-1|url=https://archive.org/details/officialiscguide0000hans/page/104}}</ref> It was developed by [[David Elliott Bell]],<ref>[http://purl.umn.edu/144024 David Elliott Bell, Oral history interview], 24 September 2012. [[Charles Babbage Institute]], [[University of Minnesota]]</ref> and Leonard J. LaPadula, subsequent to strong guidance from [[Roger R. Schell]], to formalize the [[United States Department of Defense|U.S. Department of Defense]] (DoD) [[multilevel security]] (MLS) policy.<ref>{{cite report|author1 = Bell, David Elliott|author2 = LaPadula, Leonard J.|name-list-style = amp|title = Secure Computer Systems: Mathematical Foundations|publisher = MITRE Corporation|year = 1973|url = http://www.albany.edu/acc/courses/ia/classics/belllapadula1.pdf|access-date = 2006-04-20|archive-url = https://web.archive.org/web/20060618092351/http://www.albany.edu/acc/courses/ia/classics/belllapadula1.pdf|archive-date = 2006-06-18|url-status = dead}}</ref><ref>{{cite report  |author1=Bell, David Elliott  |author2=LaPadula, Leonard J. |name-list-style=amp  |title=Secure Computer System: Unified Exposition and Multics Interpretation  |publisher=MITRE Corporation  |year=1976  |url=http://csrc.nist.gov/publications/history/bell76.pdf  |access-date=2006-03-25  |archive-date=2008-08-29  |archive-url=https://web.archive.org/web/20080829212011/http://csrc.nist.gov/publications/history/bell76.pdf  |url-status=dead  }}</ref><ref>{{cite conference
 |author=Bell, David Elliott 
 |date=December 2005 
 |title=Looking Back at the Bell–LaPadula Model 
 |pages=337–351 
 |doi=10.1109/CSAC.2005.37 
 |book-title=Proceedings of the 21st Annual Computer Security Applications Conference 
 |location=Tucson, Arizona, USA 
 |url=http://www.acsac.org/2005/papers/Bell.pdf 
 }} [http://www.selfless-security.org/presentations/lookingback/looking-back.html Slides - Looking Back at the Bell–LaPadula Model] {{webarchive |url=https://web.archive.org/web/20080608080857/http://www.selfless-security.org/presentations/lookingback/looking-back.html |date=June 8, 2008 }}</ref> The model is a formal [[state transition system|state transition model]] of [[computer security policy]] that describes a set of access control rules which use security labels on objects and clearances for subjects. Security labels range from the most sensitive (e.g., "Top Secret"), down to the least sensitive (e.g., "Unclassified" or "Public").