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Green Hills Software Extends INTEGRITY PC to Enable the Integration of Windows Applications into Secure Systems

Secure Virtualization Solution Concurrently Supports Windows, Linux, and POSIX Applications on a Single Processor

Salt Lake City, UT, SSTC—April 19, 2005
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Green Hills Software, Inc., the technology leader in operating systems and development tools for secure systems, today announced several extensions to its INTEGRITY PC Padded Cell™ secure virtualization technology that enables the incorporation of insecure and legacy software into high-security and high-reliability systems:
  • Support for Intel Architecture (Pentium) processors and commercial off-the-shelf (COTS) PC systems, in addition to PowerPC processor-based computers that were supported previously;
  • Support for Windows XP as a guest operating system, in addition to Linux; and
  • Linux binary compatibility, allowing Linux applications to be run without the need for a Linux guest operating system.

Green Hills Software is demonstrating INTEGRITY securely hosting Windows and Linux applications at the Systems & Software Technology Conference in Salt Lake City, April 18–20, 2005, in booth #326.

Built on Green Hills Software’s secure INTEGRITY operating system, INTEGRITY PC significantly reduces the time and cost required to deploy secure systems. It lets users and developers of high-security and high-reliability systems incorporate legacy applications and operating systems—including Windows and Linux—that do not otherwise satisfy a system’s security, reliability, and assurance requirements. INTEGRITY PC also supports multiple concurrent instances of the same guest operating system, each isolated in its own protected partition, allowing legacy applications running at different security levels to share the same computer.

INTEGRITY PC lets legacy applications safely share a computer with secure, native INTEGRITY and POSIX applications. (INTEGRITY is the first and only operating system to be certified under the “POSIX®: Certified by IEEE and The Open Group” program to the 1003.1™-2003 System Interfaces Product Standard and is listed on the certification register at

“With INTEGRITY PC, legacy applications—even those running at different security levels or in different security compartments—can now be integrated with one another and with the most modern, high-reliability and high-security applications on a single COTS workstation, with assured separation and information flow control,” explained Dan O’Dowd, founder and chief executive officer of Green Hills Software. “Users can create secure systems from legacy components without having to re-implement or even recompile existing applications. Legacy operating systems and applications can safely co-exist with totally reliable and security-critical applications running natively under the INTEGRITY operating system.”

INTEGRITY PC adds Padded Cell secure virtualization software to the INTEGRITY operating system. Padded Cell software implements a “virtual computer” in user-mode INTEGRITY partition. Multiple Padded Cell applications can run concurrently on a single physical computer, each hosting its own guest operating system and that operating system’s applications. An impenetrable wall around each partition ensures that errant, insecure, or malicious code can never compromise the security or reliability of the rest of the system—either inadvertently or via a hostile attack.

New Capabilities
The new INTEGRITY PC capabilities being introduced today are:

  • Support for COTS PCs based on Intel Architecture (Pentium) processors—allowing INTEGRITY PC to be used for the deployment of secure workstations, thin clients and servers based on inexpensive hardware. (See related announcement, Green Hills Software Introduces New INTEGRITY Security Products for Multilevel Secure PCs, Workstations, Thin Clients, and Servers.)
  • Support for Windows XP as a guest operating system—allowing Windows and Windows applications to be deployed safely and securely in both enterprise and embedded applications, such as automotive infotainment systems, consumer electronics, defense electronics, industrial control systems, and medical devices.
  • Linux binary compatibility—allowing applications compiled for Red Hat Linux to run in a protected, Padded Cell partition without the need for a Linux guest operating system, saving the megabytes of memory required by Linux and also increasing performance.
Key features of INTEGRITY PC include:
  • Guest operating systems and their applications cannot alter the hardware’s configuration, transfer information, or even be aware of each other except as permitted by the system’s configuration and mandatory security policy.
  • Hardware memory protection prevents software running within a virtual computer from reading or writing memory not explicitly allocated to it. Even if a virtualized application was contaminated by a buffer overrun exploit, hacker, virus, worm or Trojan horse, it would not be able to corrupt, disrupt, or spy on any other part of the system. Moreover, a hacker cannot leverage a break-in of software running in one virtual computer to gain access to the rest of the system.
  • All Input and Output (I/O) operations can be monitored, including network communications. This allows aberrant activity, such as that generated by spyware and hackers, to be detected and filtered. Because the monitoring function is performed by a native INTEGRITY application, it cannot be subverted or disabled by software running under a guest operating system.
  • Guaranteed resource availability provides each virtual computer and native INTEGRITY application with the processor bandwidth and memory required for successful execution. No software can exhaust the resources needed by another application or by the INTEGRITY operating system—thwarting any denial of service attack.
  • Completely deterministic, real-time performance is provided by the INTEGRITY operating system, enabling the co-existence of real-time and general-purpose applications.

INTEGRITY PC with support for PowerPC processors and Linux as a guest operating system is available today. Initial support for COTS PCs, Windows as a guest operating system, and Linux binary compatibility will be available in the second quarter of 2005.

About Green Hills Software
Founded in 1982, Green Hills Software, Inc. is the technology leader for real-time operating systems and software development tools for 32- and 64-bit embedded systems. Our royalty-free INTEGRITY® RTOS, velOSity™ microkernel, compilers, MULTI® and AdaMULTI™ integrated development environments and TimeMachine™ debugger offer a complete development solution that addresses both deeply embedded and high-reliability applications. Green Hills Software is headquartered in Santa Barbara, CA, with European headquarters in the United Kingdom. Visit Green Hills Software on the web at

Green Hills Software, the Green Hills logo, MULTI, INTEGRITY, velOSity, AdaMULTI, and TimeMachine are trademarks or registered trademarks of Green Hills Software, Inc. in the U.S. and/or internationally. All other trademarks are the property of their respective owners.

North American Sales Contact:
Green Hills Software, Inc.
30 West Sola Street,
Santa Barbara, CA 93101,
Tel: 805-965-6044
Fax: 805-965-6343

International Sales Contact:
Green Hills Software Ltd.
Fleming Business Centre
Leigh Road
Hampshire SO50 9PD
Tel: +44 (0)2380 649660
Fax: +44 (0)2380 649661


Media Contacts:
Green Hills Software, Inc.
Lynn J. Robinson
Tel: 805-965-6044

Green Hills Software, Inc.
Barbel French
Tel: 805-965-6044

April 19, 2005
Green Hills Software Extends INTEGRITY PC to Enable the Integration of Windows Applications into Secure Systems

April 19, 2005
Green Hills Software Introduces New INTEGRITY Security Products for Multilevel Secure PCs, Workstations, Thin Clients, and Servers
November 29, 2004
Green Hills Software Introduces INTEGRITY PC, Enabling the Integration of Linux and Other Legacy Software into Secure Systems
August 2, 2004
Green Hills Software’s INTEGRITY Operating System First to Be Certified Under the IEEE and The Open Group POSIX® Certification Program

White Paper-Apr. 2005

INTEGRITY Operating System for Secure Desktop PCs, Servers, Thin-Client Workstations, and PDAs (pdf)

EE Times-Jan. 2005
VMs tighten up PC security

EE Times-Dec. 2004
Secure Role for Linux

RTC Magazine-Sep. 2004
Operating Systems: Shouldering the Security
and Safety Burden

EE Times-Jun. 2004
Partitioning helps build system reliability

EE Times-Apr. 2004
Linux: unfit for national security?

Avionics-Mar. 2004
Real-Time Operating Systems: Versatility Plus Security (pdf)

Avionics-Mar. 2004
Keeping Secrets in Integrated Avionics (pdf)

EE Times-Aug. 2003
Designing Secure Reliable Systems

EE Times-Apr. 2002
Proper RTOS designs can improve device security