Joint Tactical Radio System poses serious security challenges

WASHINGTON — Designers of the U.S. Joint Tactical Radio System (JTRS) propose to succeed, where others have failed, in building a truly programmable, dynamically switched, multi-waveform radio.

By Charlotte Adams

WASHINGTON — Designers of the U.S. Joint Tactical Radio System (JTRS) propose to succeed, where others have failed, in building a truly programmable, dynamically switched, multi-waveform radio.

"Ten years ago this wouldn`t have been possible," says U.S. Army Col. Michael Cox, JTRS deputy program manager in Arlington, Va. The key enabling technologies behind the JTRS effort are today`s high-performance digital signal processors and controllers.

The JTRS may be a "catalyst to a new [radio] standard," Cox says. The question is, "where to define the line above which it`s open to the public and below which it`s proprietary."

JTRS is a recognition by industry and the U.S. Department of Defense (DOD) that technology advancements enable designers to develop software-programmable, digital radios not only that users can configure dynamically, but also that can play a variety of roles on the battlefield, says Ken Peterman, director of business development for tactical systems with Raytheon in Fort Wayne, Ind., head of a contractor team.

For example, users could configure the JTRS to operate lie a Have Quick radio, Enhanced Position Location Reporting System (EPLRS), or Single-Channel Ground and Airborne Radio System (SINCGARS) — like moving between e-mail and PowerPoint.

The new radio family will be capable of multiband, multimode operations and of sending and receiving secure/non-secure voice, video, and data, program officials say. Operating in the 2-MHz to 2-GHz range, JTRS will be able to send messages across geographical and organizational boundaries and will operate in point-to-point, multipoint, and multicast/broadcast modes. It will provide "interoperable, line-of-sight (LOS) and beyond LOS C4I support," the program thinking goes.

But before JTRS-architecture radios can roll off the line, program officials must satisfy several special security challenges. The JTRS architecture must be able to host security techniques in old waveforms such as SINCGARS, EPLRS, and Have Quick, Peterman says. It also needs to be able to handle various encryption/decryption techniques and transmission security techniques, such as frequency hopping and spread spectrum, appropriate to each platform, he says.

Technology is emerging that could enable users to reprogram radio channels within a radio to move to different frequencies and waveforms, and between security algorithms, Peterman says. This will enable JTRS to interoperate with different systems dynamically, on the fly. Basically, "it`s a computer with an RF front-end that transmits and receives data over an antenna, he says.

JTRS security challenges

Traditionally, communications systems "only talked to themselves," or to members of the same hardware family, Peterman explains. But JTRS devices will be able to switch dynamically from one family`s waveform to another. JTRS might talk to SINCGARS over one channel and retransmit the message to an EPLRS net over a different channel. To do this, it must be able to switch between different security techniques on demand.

Initially, security will require some hardware, Cox says. In response, Raytheon engineers are developing the Cornfield security module, a flexible, programmable, chiplike device that can reconfigure to different algorithms, Peterman says. Cornfield also provides multichannel security support to enable JTRS devices to move rapidly from one waveform to another. JTRS channels will establish the levels of security they need, Cox says.

Stopped here

Basically, two approaches to security are in the ballpark, and one or both might be chosen. JTRS might internally decrypt a message, re-encrypt it, and then retransmit it, Cox says. Or, the message might be secured end-to-end. Under the latter approach, the various JTRS radios relaying messages would never see the plain version of the message. "Both approaches have merit," Peterman says.

With a secure operating system, JTRS should be able to hold the message in the clear safely between receipt and transmit operations. The device will realize if the message is not for the operator, "refuse to show it to [him], and relay the message on," Peterman says. It knows whom the message is for. He predicts that there will be versions of JTRS that have a secure operating system and others that may not require it.

"If you had a handheld JTRS radio that was single-channel, it may not require that you have MLS [multilevel security]," Peterman says. But if it`s a radio room in an aircraft carrier, with 100 channels, "that`s a different animal." The JTRS architecture is at a high enough level "to permit implementations in many different kinds of products."

JTRS program officials launched their Phase 1 architecture definition last October and awarded 90-day, cost-shared, study contracts early this year to Raytheon, the Motorola Inc. Systems Solutions Group in Scottsdale, Ariz., and Boeing Communications and Information Management Systems group in Anaheim, Calif.

Experts submitted the studies last spring and the government selected a standard architecture definition. Raytheon officials say the standard architecture is based on their work, which contains some 40 waveforms, accommodating legacy equipment, next-generation wide-band data waveforms, and commercial personal communications systems (PCSs).

Raytheon officials say they expect to build "initial instantiations of the architecture for performance validation testing." This phase may take six to 18 months and may involve testing in different configurations, such as airborne, manpacks, and handhelds, Peterman says.

Contractors also will build "board support packages," Cox says, which will take the operating system and put in bindings that allow application programmer interfaces (APIs) and services to communicate with applications. Separation of hardware and software is also critical, he says. "You want to be able to capitalize on [technology] changes when they happen," without fundamentally redesigning the product. He also expects a database of 41 to 42 "legacy required waveforms" that can be uploaded, depending on the user`s location.

At the end of the test and validation period, "services will be released to procure digital radios for their own requirements, in accordance with the validated JTRS standard, Peterman explains. The architecture, moreover, is not protocol-specific, so it can run commercial as well as military protocols.

The procurement picture

Following congressional direction, the JTRS program, from the outset, sidestepped past radio procurement practices. In the past, the government procured individual communications systems for individual requirements. For example, government officials would buy a specific radio for ground communications that worked on a specific frequency band, with a specific waveform like that of Have Quick. The air-to-ground HQ radio used a frequency-hopping waveform. On the tactical battlefield, on the other hand, SINCGARS and EPLRS are used.

Congress stepped in with a study several years ago that said that these software-programmable radio technologies are attractive and could benefit a large number of different digital radio programs being launched across DOD. Congress directed that these programs be consolidated and that a standard be developed for programmable radios to ensure interoperability and reuse of software and hardware modules from system to system. This led to the launch of the Programmable Modular Communications System program, which then became the Joint Tactical Radio and later was dubbed JTRS.

The idea is to skinny down from an array of approximately 750,000 radios, grouped into 25 to 30 radio families - including navigation, positioning and location, identification, air/ground, air/air, ground/ground, and SatCom - to one family of joint solutions, including airborne (around 14,000 units), ground forces (approximately 293,000 units) and maritime/fixed-station (around 2,000 units).

The Joint Program Office is running JTRS architecture development. But, after the basic equipment is designed, the plan is for it to be made by numerous other companies — a paradigm shift.

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