The FACE™ open systems strategy gaining traction in the avionics industry
by Jessie Glockner , Ben Brosgol –
The Future Airborne Capability Environment™ (FACE) approach is a US government-industry initiative for reducing avionics system life cycle costs through software component reuse. The technical foundation is based on a portability-focused language-agnostic architecture and data model, common interfaces, and commercially available standards (IDL, POSIX®, and ARINC-653). The architecture comprises a number of segments -- Portable Components Segment, Transport Services Segment, Operating System Segment, Platform-Specific Services Segment, and I/O Services Segment -- that reflect a separation of concerns between portable and platform-dependent functionality.
Cost savings through reusable components is hardly a new idea, and it may look simple on the surface but has proved difficult to achieve in practice. Some hurdles are technical; designing a component for reusability requires experience and a broad set of skills, and programming languages differ in how effectively and efficiently they support reuse. And on the non-technical side, contracts for computer-based systems have historically offered little incentive, for either the agency procuring the software or the company developing it, to focus on reusability. Designing for reuse would add cost to the initial effort but realize savings only on later projects.
The FACE approach resolves this dilemma in a number of ways:
First, from the outset in 2010, it has involved all of the stakeholders: government agencies procuring avionics software, defense contractors developing the software, RTOS vendors and other suppliers of platform infrastructure, and software development and verification tool providers. The FACE Technical Standard has evolved as a consensus from these stakeholders in a “bottom-up” fashion, reflecting the state of the practice in industry.
Second, the FACE Technical Standard has taken a language agnostic approach, with support for the major languages used in airborne systems: C, C++, Ada, and (mostly for user interface components) Java.
Third, it does not attempt to address design goals other than portability. Although the FACE Technical Standard lays out operating system profiles and language subsets (“capability sets”) reflecting safety- and/or security-based restrictions, the FACE conformance tests do not check functionality, safety, or security properties. (Verification of these properties is obviously important but needs to be done separately, using appropriate analysis tools and the relevant certification standard. The SPARK Pro formal methods-based toolset is especially useful in this context, for example allowing proof that the code does not raise any exceptions.) The FACE conformance tests only check the software component and its associated data model -- officially known as a “Unit of Conformance” (UoC) -- to ensure that all interfaces are used correctly. A UoC that provides a FACE service, for example an RTOS in the Operating System Segment, has to implement all of the interfaces that the UoC’s profile requires. A UoC that functions as an application, for example flight management code in the Portable Components Segment, must only use interfaces that the UoC’s profile allows.
And fourth, reflecting the maturity of the FACE Technical Standard and the growing number of certified UoCs, DoD agencies are increasingly adding FACE conformance to the requirements for new avionics system procurements. Indeed, the FACE approach not only benefits the avionics industry here in the US, but could have a larger impact on other industries in the US and abroad as companies recognize the benefits of reusing portable technologies to provide faster, more cost-effective deployment of new systems and software platforms.
AdaCore is committed to the success of the FACE approach
Both the Ada programming language and the company’s product offerings directly support the FACE initiative’s objectives while helping developers meet the high assurance requirements that are typical in airborne software.
AdaCore has been an active contributor to both the technical and business sides of the FACE community since 2012 and is a Principal Member of the FACE Consortium. Company representatives have served as key members of the Conformance and Operating System Segment (OSS) Subcommittees, where they have reviewed the various versions of the FACE Technical Standard, helped formulate effective policies and procedures for conformance, and worked to incorporate support for Ada 2012 Safety capability sets in the FACE Technical Standard so that developers can take advantage of contract-based programming and other modern features. And just recently, Dr. Benjamin Brosgol, a member of AdaCore’s senior technical staff, was elected Vice Chair of the Technical Working Group by The Open Group FACE™ Consortium Steering Committee.
On September 21, 2020, The Open Group will host its annual FACE™ and SOSA™ (Sensor Open Systems Architecture) Consortia Technical Interchange Meeting. AdaCore is the Premier Sponsor of this year’s free, virtual event offering paper presentations by leading experts from government, industry, and academia on the use of the FACE Technical Standard and related business practices.
On March 23, 2021, The Open Group will host a live FACE™ and SOSA™ Consortia Exposition & Technical Interchange Meeting at the Holiday Inn Solomons Conference Center & Marina in Solomons, MD. This Technical Interchange Meeting will consist of keynote speakers, a panel discussion, and FACE 101 and SOSA 101 sessions. AdaCore will also be the Premier Sponsor of this event, and will be exhibiting alongside customers and partners such as Wind River, Lynx Software Technologies, Rapita, and Verocel.
- For more information about Ada, AdaCore and the FACE approach, visit: https://www.adacore.com/industries/defense/face
- For information about the FACE™ and SOSA™ Consortia TIM, September 21, 2020, visit: https://meet.opengroup.org/event/virtual-event
- For the The Open Group FACE™ and SOSA™ Consortia Expo & TIM, March 23, 2021, visit: https://expotim2021.com/