Trends in military computing

Story

October 30, 2005

A changing landscape These are good times for designers of military computer systems, as the range of choices and the breadth of applications and requirements is greater than ever before.

A changing landscape
These are good times for designers of military computer systems, as the range of choices and the breadth of applications and requirements is greater than ever before. Traditionally, military electronics have been extremely expensive, usually purpose-designed, and uniquely built for each application. Systems often do not communicate with each other, making future net centric warfare difficult. Reuse of hardware and software has been the exception rather than the norm, and design cycles historically have been long and expensive. Industry insiders often talk about the large “flywheel” in the military computer business, meaning that development cycles are long and revenues are often years away. The one open standard embraced for military applications, the VME bus, arguably has been widely accepted not for its blazing performance but rather because the standard was first published more than 20 years ago – a veritable lifetime for the rest of the computer industry.

The flywheel is still quite large, but it is rotating a bit more quickly these days. Open industry standards are becoming more popular. Former Secretary of Defense William Perry’s famous COTS directive was a factor, but the same development cost and time-to-deployment pressures that affect the commercial computer world affect military suppliers. Two PCI Industrial Computer Manufacturers Group (PICMG) standards, PICMG 1.0 (PCI-ISA Passive Backplane, 1994) and PICMG 2.0 (CompactPCI, 1995), were released 11 and 10 years ago respectively, and are used for a variety of military applications worldwide.

A wide range of open standards
PICMG’s first published specification, the PCI-ISA Passive Backplane Specification released in 1994, is being used in a wide range of applications, including the onboard fire control computer for the M109 Palladin self-propelled howitzer used extensively in Operation Iraqi Freedom. Companies  such as BES Systems Ltd. in Israel offer a complete range of ruggedized airborne, vehicle, and naval computers compliant to the PICMG 1.1 specification, additionally providing compliance to military standards including MIL-STD-810E, which dictates tough requirements for shock, vibration, humidity, fungus, salt and dust, and fog.

Released in 1995, the CompactPCI standard was developed for ruggedized industrial applications. It offered then state-of-the-art performance, based on ubiquitous PCI silicon available from virtually every microprocessor and peripheral chip manufacturer. It was based on the same IEEE 1101.1 mechanical standard used by VME, and it became very popular for communications applications worldwide. Defined for both 3U and 6U form factors, the 6U size became popular for the vast majority of communications applications, which needed every square inch of real estate for components. The 3U form factor has historically been used largely for instrumentation and some industrial automation applications but was not as widely embraced as the larger 6U form factor.

This has been changing over the last few years in a dramatic fashion. Specially ruggedized 3U CompactPCI products are being used for a wide variety of airborne, vehicle, and even space-based systems. One example is the AVC-CPCI 3009 system offered by SBS Technologies, developed for Unmanned Aerial Vehicle (UAV) applications (see Figure 1, photo courtesy of SBS Technologies, Inc.). Its integrated frame grabber and MPEG-4 image compressor connect directly to the airframe’s onboard camera, forwarding data in real time to warplanners on the ground.

Figure 1: AVC-CPCI 3009 system offered by SBS Technologies, developed for Unmanned Aerial Vehicle (UAV) applications

Systems are also going into space. Aitech’s S950 3U CompactPCI  SBC is conduction-cooled and offers a PowerPC 750FX CPU (see Figure 2, photo courtesy of Aitech Defense Systems, Inc.). It is rated to operate in Low Earth Orbit, Geosynchrounous Orbit, and Mars Terrestrial environments.

Figure 2: Aitech's S950 3U CompactPCI  SBC is conduction-cooled and offers a PowerPC 750FX CPU (photo courtesy of Aitech Defense Systems, Inc.). It is rated to operate in Low Earth Orbit, Geosynchrounous Orbit, and Mars Terrestrial environments

The 6U CompactPCI systems are also being used for military applications. Performance Technologies, Inc. builds a sophisticated Mission LAN System using the PICMG 2.16 CompactPCI Packet Switched Backplane standard.  Intended to be part of a National Command Center aboard a heavily modified Boeing 707 aircraft known as the TACAMO, it maintains communication and control in the event that other command centers are damaged or destroyed. It provides networking and routing within the aircraft, handling packetized radio, satellite, radar, and laser transmissions, and ties together different systems on the plane (see Figure 3, photo courtesy of Performance Technologies, Inc.).

Figure 3: a sophisticated Mission LAN System using the PICMG 2.16 CompactPCI Packet Switched Backplane standard.  Intended to be part of a National Command Center aboard a heavily modified Boeing 707 aircraft known as the TACAMO, it maintains communication and control in the event that other command centers are damaged or destroyed. It provides networking and routing within the aircraft, handling packetized radio, satellite, radar, and laser transmissions, and ties together different systems on the plane

Performance Technologies has also developed a unique hybrid CompactPCI/VME system for use in the Global Hawk UAV (see Figure 4, photo courtesy of Performance Technologies, Inc.). This computer provides near real-time high-resolution images and intelligence to field commanders in theater or across the world. Multicast image streams can be ordered by a commander in a control room or a soldier on the ground in the next valley, providing vital current information and situational awareness. The CompactPCI boards are conduction cooled and compliant with the ANSI/VITA 30.1 specification (2 mm connector practice for conduction-cooled Eurocard systems).

Figure 4: a unique hybrid CompactPCI/VME system for use in the Global Hawk UAV

Better architectures hit the ground
One hears a great deal about transforming the military from the current platform-centric approach to network-centric operations. The underlying computer technologies, including chips and software, are also undergoing fundamental change, and it is good news for designers and users of military computers.

Most backplane interconnect technologies, including VME and CompactPCI, are based on chip-level interconnects that were intended for planar motherboards. Hot swap was not an integral part of these interconnects, and their parallel nature has meant that any board plugged into the backplane could cause the entire system to fail if it failed. Full 2N redundancy was often the only solution. Focus was placed on reliability instead of the much more useful concept of availability because parallel bus architectures just do not adapt well to high availability designs, which require system management and failure domains of a single board. Also, as core chip voltages go ever lower, the notion of distributing chip supply voltages often means that parallel backplanes are required to produce hundreds, or even thousands, of amps of current for large systems.

This is changing for the better.  Primarily in order to increase data transfer speed, the microprocessor industry is moving rapidly towards switched serial interconnect technology, popularly known as switch fabrics. This technology reduces the speed-robbing capacitance typical of a parallel bus architecture with instantaneous point-to-point interconnects. Not only do these interconnects increase data transmission speed one or two orders of magnitude, which is important for military applications such as imaging, they can, if properly designed, reduce the failure domain to a single board or Field Replaceable Unit (FRU). They also dramatically improve the scalability of military systems, as the same packetized data format used over the backplane can be used between boxes or systems in a large network. Switched fabric Ethernet-based backplane standards, first introduced to the world in 2001 in the PICMG 2.16 Specification, are beginning to be used for military applications.

Additionally, power distribution concepts are changing with an emphasis toward shipping higher voltages across backplanes in order to reduce the ever-increasing currents required by Moore’s Law. (We’ll save cooling problems for another time.) Localized power conversion is the norm in standards like AdvancedTCA and PICMG’s recently ratified Advanced Mezzanine Card (AMC) standards.

An entire book could be written about software development, but as much as advances in this arena seem to trail hardware progress, a few things can be said. Spurred by the wide adoption of the PCI bus 10 years ago, military board suppliers are increasingly being freed from the need to write and maintain cumbersome Board Support Packages (BSPs), which often need updating every time a chip on the board changes revision. The Application Programming Interface (API) approach moves that responsibility to the chip supplier and operating system, making systems easier to upgrade and maintain. Expensive RTOSs are beginning to give way to less expensive and increasingly powerful OSs such as Real-Time Linux and Carrier- Grade Linux.

Conclusions

In the commercial communications sector, the distinction between datacom and telecom is all but gone as the world’s infrastructure moves towards packet-based communications. Military infrastructure, at least in the US, is joining the movement. Major initiatives, such as the Department of Defense’s Warfighter Information Network  Tactical (WIN-T) program, are based on commercial communication technologies, including secure wireless networks, Voice over Internet Protocol (VoIP), PCS cellular services, and ATM data transport. PDAs, laptops, and tablet computers are widely used in American command centers worldwide, and e-mail is as ubiquitous and important as it is in the civilian sector. The old notions about ruggedized military computers being completely customized boxes milled out of large bars of aluminum are changing.  And they are changing for the better as the flywheel spins faster.

Joe Pavlat is editorial director of CompactPCI and AdvancedTCA Systems. He has more than 30 years experience in the embedded computer industry. He is currently president and chairman of PICMG, an industry consortium that develops open computer standards for the industrial control, instrumentation, and communications markets. Joe holds a bachelor’s degree in computer science from the University of Wisconsin.

For further information, contact Joe at [email protected].