Other Capability Operating Systems

• Hydra served Keykos as an early cap intro.
• Mach at CMU;
• While Multics was not a capability based system, KeyKos took many ideas from Multics.
• Butler Lampson’s Reflections on an Operating System Design
• NLTSS at Livermore

Subsequent systems

• Eros is a system inspired by KeyKos, like it in many ways but with significant differences.
• Capros continues Eros.
• Coyotos spun off from EROS and partly changed directions. A comparison
• seL4
• SpeedOS
• The Hurd (Linux on Mach)
• Flask; The second paragraph of this may characterize the departure point of Flask from our perspective.
• Grasshopper, too (emphasis on persistence)
• Spring, by Sun Microsystems, is much different from KeyKos.
• We refer to this as the Monash System:
  M. Anderson, R. D. Pose and C. S. Wallace, “A Password-Capability System”, The Computer Journal, Vol. 29, No 1, 1986. Walnut; Also Password-Capabilities: Their Evolution from the Password-Capability System into Walnut and Beyond
• PSOS is a capability based OS design with careful attention to theory.
• This is about the AS/400, nee System 38, now IBM i.
• Mungi
• Security Enhanced Linux from NSA aspires to high security.
• Capabilities ‘added’ to Linux?
• TRIX at MIT (docs and source) as related by Stallman
• Backwater
• Annex
• Android has aspects of capabilities, but too much like Unix capabilities. Leaks?
• Singularity: Rethinking the Software Stack from Microsoft and note; xx
• Minix 3; Not capabilities.
• My L4 nexus
• SAFE
• Capsicum, my notes
• CHERI
• Genode, my notes, Overview, (arch)
• Barrelfish, Arch. intro, note, Wiki
• Bromium relies on VM technology.
• Sapphire
• MirageOS
• New info on Midori
• Fuchsia, Zircon, Little Kernel
• Sandstorm, a keep within Linux. (a bit like containers)

A Hydra book: William Allan Wulf, Hydra C.mmp: An Experimental Computer System, McGraw Hill,
June 1981 ISBN: 0070721203
Hydra clue.

The following book describes several capability oriented hardware systems and their software.

Henry M. Levy, Capability Based Computer Systems, Digital Press, 1984.

Juicy History of Windows