Microkernel-based and Similar Operating Systems

• Aegis/Exo-kernel (Massachusetts Institute of Technology)
  Group Members: Frans Kaashoek, Dawson Engler
  The Aegis kernel is built around the idea of an exo-kernel. An evolution from micro-kernels, exo-kernels export a virtual machine that securely multiplexes resourses among mutually distrusting spplications. The exo-kernel philosophy tries to export as few abstractions besides the basic hardware abstractions as possible, and to implement as little policy in the kernel as possible. Like SPIN, Aegis relies on techniques such as downloading code into the kernel to make the system fast.
• Alpha Kernel (Carnegie Mellon University) Group Members
• Amoeba (Vrije Universiteit)
  Amoeba is a powerful micro-kernel-based system that turns a collection of workstations or single-board computers into a transparent distributed system. It has been in use in academia, industry, and government for about 5 years.
• BE OS (Be, Inc.)
  Be is a new multithreaded, multiprocessor microkernel OS that has been designed from the ground for multimedia applications. It currently runs on the Intel and some PowerPC platforms. [ Everything I've heard about Be sounds really good. Everyone who uses it seems to be very impressed - Patrick ]
• BPMK
• Chorus (Sun Microsystems)
  CHORUS is a family of open micro-kernel-based operating system components to meet advanced distributed computing needs in areas such as telecommunications, internetworking, embedded systems, realtime, "mainframe UNIX", supercomputing and high availability. The CHORUS/MiX multiserver implementations of UNIX allow to dynamically integrate part or all of standard UNIX functionalities and services in the\ above application areas.
• COSY (University of Karlsruhe, University of Paderborn)
  Group Members: Wolfgang Burke, Roger Butenuth, Sven Gilles
  Cosy is an operating system for highly parallel computers, with hundreds or thousands of processors. All parts of the system are designed to scale up with the number of processors, without any one becoming a bottleneck.
• EROS (University of Pennsylvania) Group Members
  EROS (Extremely Reliable Operating System) is a new operating system being implemented at the University of Pennsylvania. The system merges some very old ideas in operating systems with some newer ideas about scheduling and performance. The result is a small, secure, high-performance operating system that provides transparent orthogonal persistence coupled with microkernel-style critical paths, including a high performance IPC subsystem.
• Flux (University of Utah) Group Members
  The Flux Project's objective is to develop a nanokernel-based decomposed operating system that achieves high performance while retaining inter-component protection and rich functionality. Such a system will overcome the performance/protection and performance/functionality tradeoffs that thwart traditional micro-kernel-based operating systems. This objective includes integration of selected research results of others, and free distribution of an unencumbered and usable version of the entire system.
• Harmony (National Research Council of Canada)
  Harmony is a multitasking, multiprocessing operating system for realtime control, developed at the National Research Council to serve a need for a flexible system for realtime control of robotics experiments and for other applications of embedded systems where predictable temporal performance is a requirement. Harmony is extensible, configurable and portable, both across different target computers (typically assembled from single-board computers), and across different development hosts.
• Helios (Perihelion Distributed Software)
  Helios is a micro kernel operating system for embedded and multiprocessor systems. The operating system is modular in design and can scale from an embedded runtime executive up to a fully distributed operating system.
• HURD (Free Software Foundation GNU Project)
  Related to: Mach
  The HURD is the operating system being developed by the Free Software Foundation as the basis for the GNU Project, which has already produced such well known tools as Emacs and GCC. The Hurd is a personality for the Mach micro-kernel which exports a bevy of services to the application. The Hurd will provide the standard UNIX interface, but should also be much more flexible than standard UNIX.
• KeyKOS
  KeyKOS is an operating environment for S/370 computers which provides a high level of security, reliability, performance, and productivity. It allows emulation of other environnzens such as VM, MVS, and POSIX. Development of KeyKOS ceased in 1990. Many of the ideas of this system have been carried forward into EROS
• L3 and L4
  Group Members: Jochen Liedtke
• Mach (Carnegie Mellon University)
  Mach is one of the giants in the operating systems research community. Originally started at CMU, Mach has become the basis for many research systems. Although work on Mach at CMU has largely stopped except real-time work and multi-server work, many other groups are still using Mach as the basis for research.
• Mach at OSF (OSF Research Institute)
  Related to: Mach
  The OSF Research Institute is using the Mach technology started at CMU and is using it as the basis for several areas of research, including operating systems for parallel machines, trusted object-oriented kernels, and other OS research areas.
• Mach-US (Carnegie Mellon University)
  Related to: Mach
  The Mach-US system is an OS developed as part of the CMU MACH project. It is comprised of a set of servers, each of which supports orthogonal system services. For example, instead of one server supplying all of the system services as under the Mach BSD4.3 single server (UX), the Mach Multiserver (Mach-US) has several servers: a task server, a file server, a tty server, an authentication server, a network server, etc. It also has and emulation library that is mapped dynamically into each user process, and uses the system servers to support the application programmers interface (API) of the UNIX operating system.
• Maruti (University of Maryland) Group Members
  Maruti is a time-based operating system research project at the University of Maryland. With Maruti 3.0, we are entering a new phase of our project. We have an operating system suitable for field use by a wider range of users, and we are embarking on the integration of our time-based, hard real-time technology with industry standards and more traditional event-based soft- and non-real-time systems.
• Masix (Blaise Pascal Institute MASI Laboratory)
  Group Members: Rémy Card, Franck Mével, Julien Simon
  Related to: Mach
  Masix is a distributed operating system, based on the Mach micro-kernel, currently under development at the MASI Laboratory. Its primary goal is the simultaneous execution of multiple personalities, in order to run concurrently on a same workstation applications from the Unix, DOS, OS/2 and Win32 worlds. Furthermore, Masix pools the resources of a workstation local area network, independently from the personalities that run on each node. Masix also provides distributed services to the personalities.
• QNX
  A micro-kernel, distributed, real-time, fault-tolerant, POSIX-certified OS for the x86. QNX adopts the approach of implementing an OS with a 10 Kbyte micro-kernel surrounded by a team of optional processes that provide higher-level OS services. QNX is fully distributed, with all system interfaces network transparent. QNX has successfully been used in tiny ROM-based embedded systems and in several-hundred node distributed systems.
• Real-Time Mach Project (Carnegie Mellon University) Group Members
  Related to: Mach
  Real-Time Mach is a research prototype real-time operating system intended for use as a vehicle for doing real-time systems research. The system is being developed by the ART Project in the School of Computer Science, Carnegie Mellon University.
• SPACE (University of California, Santa Barbara)
  Group Members: John Bruno, Dave Probert
  SPACE is an approach to operating systems which uses multiple protection domains rather than a single kernel to provide operating system services. Multiple instances of fundamental paradigms, such as threads and virtual memory, can coexist, since they are implemented as applications code. All that is left in what was the operating system kernel is a set of mechanisms to implement the protection domains. In SPACE these mechanisms.can be replaced as needed by the application to provide a fundamental level of extensibility not available in other adaptive operating systems.
• SPIN (University of Washington) Group Members
  SPIN is one of several research systems that aims toward run-time flexibility and specialization using techniques like type-safe languages and dynamic code generation to make a fast, dynamic, flexible system. It is an extensible operating system micro-kernel that supports the dynamic adaptation of system interfaces and implementations through direct application control, while still maintaining system integrity and inter-application isolation.
• Spring Real-Time Project (University of Massachsetts, Amherst) Group Members
  The Spring kernel has been designed and implemented to support/provide predictability, on-line dynamic guarantees, atomic guarantees, end-to-end scheduling and resource reservations. It utilizes a micro-kernel design for multiprocessor architectures and provides an interface to remote processes, support for distributed shared memory, and predictable low level communication. The kernel exists as a component of Spring's integrated environment. This environment extracts significant semantic information and this information is used at runtime to support flexibility. (ed: This is not the same as the Spring OS from Sun, which unfortunately has the same name.)
• Spring System (Sun)
  Sun's new research kernel. Spring is a highly modular, object-oriented operating system, which is focused around a uniform interface definition language. Spring is intrinsically distributed, with all system interfaces being accessible both locally and remotely.
• Sumo (Lancaster University)
  Related to: Chorus
  Over the past few years members of the SUMO team have been designing and implementing a microkernel based system with facilities to support distributed real-time and multimedia applications and ODP based multimedia distributed application platforms. We are interested in both communications and processing support for distributed real-time/ multimedia applications in end systems, and believe that such applications require thread-to-thread real-time support according to user supplied quality of service (QoS) parameters.
• Tao Operating System (Tao Systems) Group Members
  Tao is a radical commercial operating system or run time module offering all of the features required for the building of leading edge, cost driven, embedded consumer electronics (single and multi-processor). It is available on a broad range of processors both as a stand alone OS and co-existing with host operating systems.
• VSTa
  VSTa is an experimental kernel which attempts to blend the design of a micro-kernel with the system organization of Plan 9. The result is a small privileged kernel running user-mode tasks to provide system services such as device drivers, file systems, and name registry. Like Plan 9, each service provides a file system-like interface.