Hydra (operating system)
{{Infobox OS
| name = Hydra
| logo =
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| developer = Carnegie Mellon University
| family = Capability-based
| working state = Discontinued
| source model =
| released = {{Start date and age|1971}}
| discontinued = Yes
| latest release version = Final
| latest release date = {{Start date and age|1975}}
| marketing target = Research
| programmed in = BLISS
| language = English
| update model = Compile from source code
| supported platforms =
| kernel type = Microkernel
| userland =
| ui = Command-line interface
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Hydra (stylized as HYDRA) is an early, discontinued, capability-based, object-oriented microkernel designed to support a wide range of possible operating systems to run on it.Wulf 74 pp. 337–345 Hydra was created as part of the C.mmp project at Carnegie Mellon University in 1971.{{cite book
|last1=Siewiorek |first1=Daniel P. |author1-link=Daniel Siewiorek
|last2=Bell |first2=C. Gordon |author2-link=Gordon Bell
|last3=Newell |first3=Allen |author3-link=Allen Newell
|last4=Mashburn |first4=Henry M.
|year=1982
|title = Computer Structures: Principles and Examples
|url = http://research.microsoft.com/users/gbell/Computer_Structures_Principles_and_Examples/csp0366.htm
|place = New York, New York
|publisher = McGraw-Hill}}
The name is based on the ancient Greek mythological creature the hydra.
Hydra was designed to be modular and secure, and intended to be flexible enough for easy experimentation.{{cite book
| last = Levy
| first = Henry M.
| year = 1984
| title = Capability-Based Computer Systems
| url = http://www.cs.washington.edu/homes/levy/capabook/Chapter6.pdf
| publisher = Digital Press}}
The system was implemented in the programming language BLISS.{{cite report |first1=William A. |last1=Wulf |author1-link=William Wulf |first2=Samual P. |last2=Harbison |title=Reflections in a pool of processors: An experience report on C.mmp/Hydra |url=http://www.cs.auckland.ac.nz/compsci703s1c/resources/WulfHarbison.pdf |page=945}}
References
{{Reflist}}
- {{cite book |last1=Levin |first1=R. |last2=Cohen |first2=E. |last3=Corwin |first3=W. |last4=Pollack |first4=F. |last5=Wulf |first5=William |author5-link=William Wulf |date=November 1, 1975 |chapter=Policy/mechanism separation in Hydra |title=Proceedings of the fifth ACM symposium on operating systems principles |pages=132–140 |doi=10.1145/800213.806531|s2cid=10524544 }}
- {{cite journal |last1=Wulf |first1=William |author1-link=William Wulf |last2=Cohen |first2=E. |last3=Corwin |first3=W. |last4=Jones |first4=A. |last5=Levin |first5=R. |last6=Pierson |first6=C. |last7=Pollack |first7=F. |date=June 1974 |title=Hydra: The Kernel of a Multiprocessor Operating System |journal=Commun. ACM |url=https://dl.acm.org/doi/10.1145/355616.364017 |volume=17 |issue=6 |pages=337–345 |doi=10.1145/355616.364017 |s2cid=8011765 |url-status=live |archive-url=https://web.archive.org/web/20070701203145/http://www.cs.princeton.edu/~rywang/02f518/papers/hydra.pdf |archive-date=July 1, 2007}}
{{Object-capability security}}
{{Microkernel}}
{{Operating-system-stub}}
Category:Carnegie Mellon University software