News & Press

Green Hills Software Introduces New INTEGRITY
Security Products for Multilevel Secure PCs,
Workstations, Thin Clients, and Servers

Support for Multiple Concurrent Security Levels on COTS Computers
Enable Integration of Legacy Command and Control Systems

Salt Lake City, UT, SSTC—April 19, 2005—Green Hills Software, Inc., the technology leader in operating systems and development tools for safe and secure systems, today introduced INTEGRITY Workstation, INTEGRITY Thin Client, and INTEGRITY Server, new products for network and enterprise use that let applications running at different sensitivity levels run securely on a single commercial off-the-shelf (COTS) personal computer or server. Based on Green Hills Software’s proven INTEGRITY operating system, these products enable secure integration of multiple legacy command and control systems and support the development of new, multilevel secure (MLS) systems and cross-domain solutions (CDS). Additionally, they enable secure web services for communication on the Global Information Grid (GIG).

Green Hills Software is demonstrating these new products at the Systems & Software Technology Conference in Salt Lake City, April 18–20, 2005, in booth #326.

INTEGRITY Workstation, INTEGRITY Thin Client, and INTEGRITY Server significantly reduce hardware and administrative costs while improving users’ access to information and applications by allowing functions that previously required multiple computers to be integrated into one. In the past, users of secure systems needed multiple computers to access information from multiple security domains or at multiple security levels—for example Top Secret, Secret, and Unclassified. Up to now, security required physical separation because traditional computer operating systems did not provide adequate security to ensure information with different sensitivity levels would remain segregated within a single computer.

A Secure Foundation

Green Hills Software’s INTEGRITY operating system was designed specifically to provide the level of assurance required to support multilevel and cross-domain security on a single computer. INTEGRITY employs a layered, high-assurance Multiple Independent Levels of Security (MILS) architecture with a small separation kernel at its core. INTEGRITY is now undergoing the most stringent security evaluation undertaken by any operating system, to Common Criteria Evaluation Assurance Level 6+ (EAL6+). On the seven-level assurance scale, no operating system has previously been certified beyond EAL5. (See related announcement, Green Hills Software Selects SAIC for EAL6+ Security Evaluation of the INTEGRITY Operating System.)

Available since 1997, the INTEGRITY operating system has been selected for some of the United States’ most security-critical and safety-critical systems, including the Joint Tactical Radio System (JTRS), B-1B bomber, F-35 Joint Strike Fighter, and Boeing X-45C Unmanned Combat Air Vehicle (UCAV). Green Hills Software’s new INTEGRITY security products, introduced today, deliver the security provided by the INTEGRITY operating systems to COTS PCs, workstations, thin clients, and servers.

“Green Hills Software now provides a scalable security solution that addresses the full range of computing environments, from enterprise servers to small, resource constrained embedded systems,” commented Dan O’Dowd, founder and chief executive officer of Green Hills Software. “For more than seven years, the INTEGRITY operating system has been used to fly planes, secure military radios, and make smarter medical devices—among many other mission-critical applications. Now, users of COTS computers can take advantage of the well-established, unbreakable security and total reliability of INTEGRITY.”

New Security Products

The new security products introduced today are:

  • INTEGRITY Thin Client—Runs on COTS diskless PCs. INTEGRITY Thin Client is configured with secure client communication software that can be connected to remote servers or workstations running at different security levels. INTEGRITY Thin Client can be software-upgraded to INTEGRITY Diskless Workstation or hardware- and software-upgraded to INTEGRITY Workstation.
  • INTEGRITY Diskless Workstation—Provides all thin client and workstation capabilities, including the ability to securely run Windows and Linux applications. Boots, loads applications, and stores data through the network rather than on a local hard drive.
  • INTEGRITY Workstation—Provides all the software needed for a secure workstation, with support for securely running Windows and Linux applications on COTS PCs.
  • INTEGRITY Server—Meets the need for high-performance, multilevel secure network servers. INTEGRITY Server can run multiple independent instances of Windows and Linux in addition to applications written to INTEGRITY and POSIX interfaces. INTEGRITY Server applications can communicate with local users who use INTEGRITY Workstation or INTEGRITY Thin Client, or who use conventional workstations and thin clients. INTEGRITY Server includes a comprehensive set of secure systems services to help integrate legacy systems and managing network services on a multilevel secure network.

New Middleware Components

INTEGRITY Workstation, INTEGRITY Thin Client, and INTEGRITY Server include the INTEGRITY operating system, secure file system, multilevel network stack, and new middleware components, including:


The INTEGRITY Desktop manages the display of information at multiple security levels. The included INTEGRITY Window Manager provides secure, unforgeable window labels and also supports a multilevel secure, cross-domain information transfer “cut and paste” capability that can be customized to support application or system-specific security and re-grading policies. The INTEGRITY Window Manager provides secure login and authentication and supports smart cards and other access devices used in conjunction with login.

INTEGRITY Device Manager

The INTEGRITY Device Manager controls access to devices, such as the keyboard, mouse, and video screen, preventing the unauthorized flow of information across security domains. The INTEGRITY Device Manager and INTEGRITY Window Manager are synchronized so that devices communicate only with the currently active window.

Padded Cell Secure Virtualization for Windows and Linux

Padded Cell secure virtualization allows Windows and Linux to run as “guest” operating systems within protected partitions of the INTEGRITY operating system. Guest operating systems run in a processor’s user mode and have no direct access to hardware. Consequently, they cannot affect the security policies enforced by INTEGRITY. All input and output is virtualized by the Padded Cell software and carried out only in accordance with system security policies. Multiple instances of the same guest operating system can run concurrently, each operating on information at a different security level. (See related announcement, Green Hills Software Extends INTEGRITY PC to Enable the Integration of Windows Applications into Secure Systems.)


Initial versions of INTEGRITY Workstation, INTEGRITY Thin Client, and INTEGRITY Server 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