Storage trends in the trenches

Dec. 1, 2006
The latest advancements in portable, rugged data storage are designed to deliver critical data to warfighters on the battlefield quickly, securely, and without fail.

The latest advancements in portable, rugged data storage are designed to deliver critical data to warfighters on the battlefield quickly, securely, and without fail.

By Courtney E. Howard

“In the Information Age, power is increasingly derived from information sharing, information access, and speed-all of which are facilitated by networked forces.” These were the words of retired U.S. Navy Vice Adm. A. K. Cebrowski, former director of the Pentagon’s Office of Force Transformation.

Information lies at the heart of network-centric warfare, a central focus of Cebrowski and his former organization. Cebrowski died of cancer in November 2005, but he left a rich legacy of doctrine and ideas to transform the U.S. military into a 21st century fighting force.

The success of network-centric warfare relies on the ability to provide the right information to the right people at the right time. As a result, attentions have turned to the issue of data storage and the needs of the warfighter, including fast, reliable access to an ever-increasing amount of mission-critical data. After all, in the battlefield environment, data access could mean the difference between mission success and failure, or life and death.

It remains a central tactical and technological challenge to provide the data storage necessary for warfighters and decision makers to operate effectively in the field. Data-storage vendors continue to invest heavily in research and development to better serve military and aerospace systems designers and their specialized needs and applications.

Data density

Data-storage needs in general increase at a rate of roughly 40 percent year over year. “Demand for storage capacity in the military is tracking the expectations of comparable commercial applications,” says Sam Carswell, chief technical officer at Formation Inc. in Moorestown, N.J. “The need for capacity continues to press the computer industry to obey Moore’s Law.”

In military environments, including the battlefield, the content of the data is varied, notes Ken Owens, chief executive officer and president at Conduant Corp. in Longmont, Colo. “It is more than just images and video,” he says. “It is sensor data, such as radar, radio signals, and more that are being digitized and stored for subsequent processing and analysis.”

Formation’s ToughDisk 3500 rugged hard disk drives are incorporated into Deep Development Corporation’s Viperfish ASX digital video recorders aboard U.S. Air Force AC-130H/U gunships.
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This data-critical information for warfighters on the battlefield-must be delivered quickly and reliably, and often for extended time periods. “Military customers tend to need higher data rates and/or longer duration than commercial customers,” Owens continues. “Military applications may also have special requirements, such as low power usage for battery operation or ruggedization levels, not required in the commercial sector.”

Military customers not only require as much, if not more, storage capacity as today’s commercial user, but also must take into consideration a variety of other traits, such as a solution’s size, weight, and power (SWaP) and its ability to withstand harsh environmental conditions.

Beyond COTS

“We see the military decidedly going as much as possible with commercial off-the-shelf equipment, even in the battlefield,” Carswell says. “You’ll see 19-inch rack Dells and Hewlett-Packards out in the field because that equipment is quite good these days.” However, commercial off-the-shelf (COTS) data-storage solutions must be infused with other technologies to work in a deployed military application. Carswell’s team at Formation, as an example, wraps its technology around COTS disks.

The failing part on the battlefield very often is the disk drive, partly from the high-temperature, dirty environment in which it is used. “They breathe air and that air goes into the disk itself, the motor, and the flying head, so dirt is a bad thing,” Carswell explains. “We seal them so they have U.S. air inside them at one atmosphere for the life of the drive. They are always using clean air.”

Drives also can fail in the field due to handling of the drive, whether during shipment, use, or repair. Shock and vibration can damage or destroy a storage device, so ruggedized solutions are key to battlefield scenarios.

Manufacturers can ruggedize a storage drive externally, such as with rugged carriers and mounting hardware, or internally, involving the mechanics of the disk itself. Mechanical drives are more susceptible to shock and vibe because they use moving parts, so storage vendors to the defense community and the end users themselves take steps to safeguard the devices and ensure their operability.

M-Systems’ solid-state drives are employed in Bradley vehicles as part of the Force XXI Battle Command Brigade and Below (FBCB2) tactical computer.
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“A piece of that vibration/shock element is to bring the high performance that these drives offer, but let that not be degraded excessively by vibration and shock,” Carswell remarks. Formation product engineers, for example, equip the company’s ToughDisk 3500 (TD3500) with an internal shock system yet it doesn’t deal with the issue of vibration. In high-vibration environments, customers often mount the drive in a rack of equipment or to the combat vehicle itself, as when bolting down a hard drive in an aircraft.

Shock and vibe is a significant concern, one that is only exacerbated by the growing desire for removable storage options in the military. Military customers favor removable storage solutions not only because they increase information security by protecting data from getting in wrong hands, but also improve data accessibility. If hardware goes down, whether a computer system or an entire tank, the removable storage device can be inserted into another system quickly and easily.

“The real danger is that suddenly the drive, whether solid-state or hard disk, is in someone’s hand,” Carswell points out. “Any device that has suddenly left the protective cocoon of the equipment that it’s mounted inside and is in someone’s hand is probably at its most vulnerable time in life.” Removable drives are susceptible to static electricity, which solid-state drives don’t react to well, and shock and vibration from being jostled around or dropped. Off-the-shelf hard drives are quite fragile, admits Carswell, but a device’s handling shock can be increased well above what a standard disk drive can handle. And the option of using a flash drive also exists.

A drop-in replacement for the hard disk drive with no moving parts, M-Systems’ Ultra ATA solid-state drive is field-tested to provide a far superior solution for defense applications that must operate reliably in harsh conditions of shock, vibration and temperature extremes.
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“The mechanical hard drive has moving parts and delicacy involved, whereas the solid-state system uses small chips, so doesn’t suffer from the kind of mechanical failure that hard drives do,” says Rochelle Singer, marketing and technical documentation manager of embedded systems at msystems Inc. in Sunnyvale, Calif.

Mechanical storage can be a headache for warfighters, such as the U.S. Army brigade deployed in Iraq, who rely on stored data, adds Ofer Tsur, vice president of SSD (solid-state drives) within the embedded business unit of msystems. “It’s hard to maintain and replace a hard drive, inside of which is configuration data that you don’t want to lose,” he says. “The military certainly can’t deal with maintenance in the field,” Singer agrees. “This is one of the biggest disadvantages of hard drives.”

M-Systems’ mDOC H3 family of embedded flash drives are incorporated in ultra wearable computers for military applications.
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Formation’s Carswell admits that mechanical solutions are not efficient in environments where the vibration is too high. “A fighter jet is not a place where one would readily stick a hard drive, even with our technology,” he acknowledges. “There exist environments that are even beyond what we can do and what we think is wise to do, frankly. In those cases, you’ve got to go for solid state, but you pay the price. Like in life, if something will do the job, then you pick the piece that solves the problem for the lowest price.”

SWaP specs

Price, though a concern, is eclipsed by the need for a solution that takes into account the size, weight, and power constraints faced by today’s warfighter. Yet a drive’s much-needed ruggedized characteristics can influence its physical specifications.

It has not been uncommon for companies to enclose a commercial hard drive in rigid casing to improve its ability to withstand harsh environmental conditions, including shock and vibe, dust and dirt, temperature, and humidity. “Ruggedization made the total solution three times bigger in size, five times greater in weight, and more expensive,” says msystems’s Tsur. For military applications, each of these-size, weight, and cost-is an important consideration.

“Power consumption is another issue,” admits Singer. “Flash drives save more power than hard drives.” She insists that a solid-state drive consumes as little as one tenth of the power used by a hard drive. The issue of one device’s power consumption over another might not be so cut and dried, however.

Heim Data Systems’ data recorders use M-Systems’ solid-state disks inside ruggedized housings to extend their ability to withstand environmental stress and temperature extremes in mission-critical applications.
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Carswell and his Formation colleagues find that, at higher capacities, mechanical drives are likely to have lower wattage than their solid-state counterpart.

“With solid state, the entire disk is typically powered up, ready to access any piece of the data,” he explains. “In the mechanical disk, the platters draw no power. The more data you stick on the platters, the more data you have, but no extra power is required.”

A Formation 3.5-inch disk drive provides roughly 80 gigabytes per watt, for example. A 160-gigabyte drive, he argues, has low wattage for a lot of capacity, readily available for immediate use-translating to a lower-power and faster solution than even tape storage. Of course, tape storage is not an option. Warfighters in ground, sea, and air missions-whether inside or outside a combat vehicle-require efficient, reliable, and portable solutions.

On the ground

In the past, the U.S. Army incorporated mechanical hard drives in Bradley Fighting Vehicles; due to high failure rates and high costs of maintenance, Army personnel have opted to use solid-state drives.

“They were using a standard hard drive, which is rotating media,” Tsur notes. “Due to the high shock and vibration, after a few minutes of operation while driving in the Bradley, they experienced a failure in the hard drive. They had to switch to a solid-state drive. We provided them an identical solution in terms of form factor and interface, so the integration was fairly easy. They swapped out the drives in an easy upgrade.”

Each Bradley in the U.S. Army’s Force XXI Battle Command, Brigade-and-Below (FBCB2) program, in fact, employs a rugged computer with a solid-state flash drive, Tsur says. DRS supplies the FBCB2 computer systems, which are employed in and enable communication among all sorts of combat vehicles and improve warfighters’ situational awareness by supplying maps with friends and foes delineated by color.

This airborne Joint Surveillance Target Attack Radar System (Joint STARS) Operator Workstation takes advantage of a removable hard-disk-drive system from Phoenix International.
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Bradley crews need to refresh data readily and gain real-time feedback. Because data read and write times are critical on the battlefield, speed is another important storage consideration. The msystems solid-state solution for the FBCB2 program incorporates an Ultra DMA5 interface, capable of providing up to 100 megabytes per second read and write speeds.

To ensure the security of data in the field, the drives in the Bradley vehicles use the msystems Quick Security Erase and Sanitize. This security feature enables users to sanitize the drive, or purge all the confidential data, in seconds. In the case of an emergency, Army personnel can erase the drive and ensure that no confidential information gets into the wrong hands during an operation.

Phoenix International, credited with pioneering rugged removable mass storage, offers transportable storage solutions for the military. Among them is the rugged, portable Phoenix Fibre Channel storage-area-network (SAN) system.
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The sole supplier for the solid-state flash drives used in the DRS FBCB2 computer systems is msystems, which is shipping thousands of drives each year for the FBCB2 program alone. Prior to being implemented in Bradleys as part of the FBCB2 program, msystems’s solid-state drives were subjected to shock and vibration tests and temperature cycling. A mandatory requirement for the drives is the ability to operate under and withstand harsh environmental conditions, including high temperatures, humidity, and extreme shock and vibration. msystems’s drives not only comply with military standards for shock and vibration, but also support the industrial-grade temperature range.

Seafaring storage

Seafaring and underwater applications likewise have stringent environmental requirements. Formation designed its Advanced Integrated Recorder (AIR) systems, part of a submarine communications system, to survive the submarine’s humidity, pressure, and shock requirements. The AIR system combines commercial off-the-shelf (COTS) rackmount servers with Formation’s TD3500 hard drive.

“By replacing standard hard disks with ToughDisks in our existing COTS server, we were able to meet both the recording requirements and difficult environmental requirements of our customer’s naval application,” explains Doug Crawford, Formation’s product director.

“Our TD3500 ToughDisk is a rugged, drop-in replacement for standard 3.5-inch hard drives, and our AIR system uses COTS servers that easily accept ToughDisk,” notes Nim Evatt, Formation’s chief executive officer. “The result is a much more survivable computer through the elimination of its weakest element-an unprotected hard disk.”

The VMETRO SANbric provides more than a terabyte of storage capacity in a sealed, shock-isolated package aboard unmanned aerial vehicles (UAVs).
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The TD3500 hard disk is the exact same size, uses the same connectors, and has all the same electrical and physical characteristics as a standard drive one might buy commercially. Military customers can integrate the drives into standard equipment with no design work.

The AIR system and ToughDisk models TD3500 and TD7200 also address the growing demand for cost-effective data storage capacity and performance in harsh airborne environments. The solutions are used in air traffic control, air defense, and command-and-control centers to record, store, and replay synchronized workstation screen activity, radar, local-area-network, and voice data.

Airborne assets

Deep Development Corp. in Abbotsford, British Columbia a division of Gatekeeper Systems Inc. in Irvine, Calif., integrated Formation’s ToughDisk 3500 rugged hard disks into Viperfish ASX high-resolution digital video recorders aboard U.S. Air Force AC-130H/U gunships. Air Force personnel use the device to record planes in action as they escort convoys, protect air bases and facilities, and carry out air strikes. Air Force officials also use the recorded data to review operations.

ToughDisk rugged hard disks are removable data storage units built specifically to withstand extreme temperature, shock, vibration, humidity, and dust conditions. In fact, the ToughDisk 3500 was selected, for its ability to perform reliably in extreme environments, says Doug Dyment, chief executive officer and president of Gatekeeper Systems.

“Formation’s ToughDisk has been used in submarine, shipboard, and airborne defense applications because of its performance characteristics and its cost and capacity advantages over solid-state storage,” says R. Nim Evatt, chief executive officer and president of Formation.

Heim Data Systems in Belmar, N.J., on the other hand, elected to employ a solid-state flash drive in its high-end data recorder, which has been shipped to such customers as Lockheed Martin and EADS for use on military aircraft. The Heim system takes advantage of an msystems’s flash drive with an Ultra SCSI interface capable of 320 megabytes per second read and write speeds and of simultaneously recording multiple channels of video and audio with compression.

Sky-high systems

Certainly, storage solutions in airborne military applications must comply with altitude requirements.

“A standard hard disk is specified typically at 10,000 feet, but it’s not hard to get above 10,000 feet in the military,” says Formation’s Carswell. For this reason, Formation’s ToughDisk 3500 supports altitudes of up to 50,000 feet, satisfying the requirements of most military customers. At the same time, msystems’s solid-state drives support extreme altitudes, and are being shipped in mass production for data-recording applications aboard F-15s and F-16s, B-1s, and B-2s, and other military aircraft.

Aircraft-related space and weight constraints often are not present in many ground situations, points out msystems’s Singer. “If you need to ruggedize a hard drive by putting it in a container that makes it more resistant to vibration and shock, it adds weight and space,” she says. “Flash storage doesn’t need that because it is characteristically rugged.”

As a result of space and weight constraints, whether in vetronic, airborne, unmanned, or wearable applications, producers of data-storage solutions continually strive to condense more and more storage density in a very small form factor.

“Our ability to provide high density in a small form factor is a key feature for our customers,” Tsur notes. “In a one-inch SCSI drive today, we can provide 352 gigabytes. In July 2007, msystems engineers intend to double the storage capacity, providing 704 gigabytes in a one-inch unit.

Formation’s TD3500 hard disk offers 160 gigabytes of storage capacity in a 3.5-inch form factor. The device’s storage capacity will double to more than 300 gigabytes in mid-2007, and it will increase by another 25 percent by the end of 2007.

Unmanned data

Perhaps no vehicles suffer more size, weight, and power constraints than unmanned craft. This is a well-known fact, says Tom Bohman, vice president of business development for I/O and recorder products at VMETRO Inc. in Houston. Bohman is involved in the integration of VMETRO storage solutions with unmanned air vehicles (UAVs).

“Ruggedization is a must because the environment does not need to be manned,” Bohman says. “Altitude and temperature extremes must be tolerated that do not exist in manned aircraft.” Speed and capacity are equally important to SWaP in flying platforms, he continues. Today’s electronic sensor systems capture massive amounts of data at very high speeds and data storage devices have to keep pace, which requires increased data density and read/write speeds.

“Many UAVs are intelligence, surveillance, and reconnaissance (ISR) platforms and as such gather an enormous amount of streaming data from an array of sensors that monitor the outside world,” Bohman points out. “Much of this data is processed in real time and telemetered to the ground station.”

The telemetry link often has limited bandwidth, so the desire to bring home large amounts of data for post-mission analysis always exists. As a result, most ISR storage solutions and data recorders require easily removable and transportable storage devices. These traits ensure data can be readily delivered to the ground station for post-run review, enable users to reload and re-launch the ISR platform with new storage capacity quickly, and avoid the lengthy downtime associated with downloading many terabytes of data from an unmanned craft.

Cost is another critical factor, Bohman says. Because solid-state storage remains on the order of 10 times more costly per gigabyte than rotating media, attentions turn to ruggedized rotating media products. Among these solutions is the VMETRO SANbric, which offers 1.8 terabytes of capacity in a sealed and shock-isolated package well-suited to the nonviolent environments of most UAVs.

“Ruggedized rotating media and solid state are both viable solutions to UAV storage and data recording requirements,” Bohman admits. “The decision will be based on size, weight, power, environmental, and cost considerations. There is no silver bullet, only an array of weapons from which to choose.”

On-soldier solution

The options are also many, varying in weight and size to a considerable degree, when it comes to storage solutions for wearable computers.

The msystems DiskOnChip (DOC) embedded flash drive product line, which it ships to makers of wearable computers, includes very small data storage solutions measuring 7 by 9 and 9 by 11 millimeters-both smaller than one-half square inch. “We can provide in a very small VGA package up to 2 gigabytes of data storage,” Tsur says. “Today, third-generation mobile phones are using our devices, which are very small, very rugged, and ideal for wearable computers.”

An msystems DOC can store, for example, an operating system and application information, mission data, maps, and so on. The company is shipping solid-state disks as hard-drive replacements in rugged computers, as well as data recorders, radar and sonar systems, and servers.

Mechanical or solid-state?

Mechanical and solid-state drives deliver data storage to armed forces personnel in myriad hardware devices-from rugged laptops to tactical computers, rugged servers, and digital recorders-and in an even greater number of defense applications. With so many data storage options available, it can be challenging to select the optimal solution for each task.

On one hand, solid-state storage vendors tout that the popularity and ever-expanding adoption of flash drives in MP3 players, digital cameras, mobile phones, USB drives are bringing about price reductions on the order of 50 percent per year. This factor makes the solid-state flash drive much more attractive, as does the fact that its storage capacity doubles with each passing year.

On the other hand, mechanical disk drives boast very high capacities, which are necessary in military applications, accompanied by a small price tag. “Ten times less expensive than solid-state disk, ToughDisks enable the fielding the data-intensive high storage capacity applications,” Carswell notes. “ToughDisks don’t match solid-state disks’ environmental specifications, but ToughDisk environmental specifications match many battlefield applications and can deliver capacity that isn’t practical for solid-state disks. ToughDisks and solid state disks complement each other.”

“I don’t think solid-state will negate the need for magnetic media any time soon,” says Conduant’s Owens. “The cost per megabyte of magnetic disk is continuing its long historic downward trend. Although solid-state media is becoming more affordable, there is still a significant gap. Certainly smaller disk drives are the trend, driven by portable music players and soon automotive applications, and optical media continues to lag behind magnetic disk in performance and capacity. Even with new breakthroughs in optical technology, the breakneck speed of magnetic disk development continues to eclipse the commercialization of these technologies due to the massive manufacturing capability of the magnetic disk manufacturers.”

Thanks to new disk technology, users can benefit from the strengths of both mechanical and solid-state data storage devices. Next month’s debut of the Microsoft Vista operating system from Microsoft Corp. in Redmond, Wash., is expected to herald the widespread adoption of a new storage technology: hybrid disk.

A new innovation, the hybrid disk drive, satisfies many requirements of military applications, such as low energy consumption and external shock absorption, by incorporating the advantages of flash technology into a hard disk drive. The hybrid drive combines non-volatile cache with a conventional hard disk drive, and is the first release to combine a magnetic storage device with digital semiconductor technology. Hybrid technology offers faster system boot and response times, faster resume from hibernate, increased read and write speeds, high reliability, and power savings.

Data storage applications are infinite, as are peoples’ imaginations, Carswell observes. “I never see someone being satisfied with the amount of storage provided them because applications can always take more,” he says. “People want to have more data, more readily at their fingertips.”

Carswell uses the example of storing and accessing digital map data. “At one time, maps didn’t take much storage space because they were simple little stick drawings. Now it’s very realistic to believe that people will expect to have Google Map or its equivalent at their fingertips. Why wouldn’t they expect to have that quality in the battlefield when that’s what they can get at home? The amount of information you gain through that type of content is so much greater and gives you such a better feel for it, but it’s a huge amount of data. I think storage capacity, regardless of the application, will continue to track Moore’s Law-and we’re going to struggle to keep up with it. When I look forward, I can’t imagine what that means. It seems without end.”

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