The Solid State Alternative
Written by Peter A. Buxbaum
As prices fall and capacities increase,
solid state drives are making more inroads
into military data storage applications.
Logically, such an operation ought to be accomplished with the push of a button or by entering a simple command. Instead, the crew was forced to use axes against the systems in order to prevent their Chinese captors from gaining access to sensitive data.
The crew had to physically destroy the storage media because most of the data gathering systems on the aircraft in question employ hard disk drives like those found in most home and office computers. It is nearly impossible to completely erase a hard disk, and any erasure would take too long in an emergency situation. That’s why the axes came out.
These days, growing numbers of military computing systems, and some commercial ones as well, are employing solid state drives (SSDs) as an alternative to the hard drives familiar to anyone who owns a personal computer. While SSDs have had a niche in high-end military systems for some time now, usage is expected to expand greatly as prices continue to fall.
Data decimation may seem an unusual place to start a consideration of data storage media, but the need to destroy sensitive data in emergency situations is a real-life security consideration for which the U.S. military has regulations and procedures. If the naval aviators had had SSDs on board their aircraft, they could have completely erased their data with the push of a button.
That is only one aspect by which solid state drives are distinguished from their older, hard-drive counterparts. At the physical level, SSDs contain no moving parts and employ flash memory, a nonvolatile medium that stores data on chips and requires no power to maintain. Hard drives, by contrast, consist of a spinning disk and a moving arm with a read/write head. The lack of moving parts means that SSDs are a more stable medium than hard drives, consume less power, emit little if any heat, and provide quicker access to data. They have other advantages as well.
EXTREME ADVANTAGES
The military often must sustain operations in extreme environments, where SSDs are far more reliable. They excel at high altitudes and when exposed to humidity, temperature, sand, dust and vibration. Ordinary hard drives, by contrast, must be specially ruggedized and protected to meet military criteria.
SSDs also increasingly incorporate leading-edge data security features that comply with rigorous military security standards and are very small in size.
U.S. military systems have incorporated solid state storage subsystems in applications such as aircraft data recorders, image exploitation computers, navigation systems and on vehicle-mounted computers. Falling prices and higher storage densities could push SSDs out to applications carried by small units of dismounted soldiers, such as wearable PCs.
“Solid state storage is a disk drive that has no moving parts,” said Gary Drossel, director of product planning at the solid state storage business unit of Western Digital Corp. “No moving parts means the medium itself is not volatile, and makes it more reliable when exposed to shock, vibration, high temperatures and other environment factors. Other than that, they look just like other disk drives and use standard interfaces.”
“SSDs are 100 percent solid state, providing a minimum of 1,000 G shock resistance,” said Troy Winslow, director of product marketing at Intel Corp.’s flash memory products group. “With no moving parts, Intel’s SSDs provide more than 900 percent performance improvement over standard hard drives, meaning that the systems boot faster, open and close applications faster, consume less power, and can be operated on the go regardless of the environment, which is critical for military applications.”
And as far as the erasure capability goes, “It is built into the control system of the drive,” explained Roydn Jones, vice president for advanced products at Trident Space & Defense, a provider of solid state drives and other products. “It is like pushing a panic button. The computer will erase all of the data in tens of seconds. Other memories erase more slowly, and there is inevitably some remnant of the data left on the drive.”
The key factors preventing every military computer, or home or office computer for that matter, from being equipped with SSDs have been price and density. “The costs of solid state drives are still significantly higher,” said Amos Deacon, president of Phoenix International Systems, a manufacturer of storage systems. “You can buy a single hard drive with 2 terabytes of capacity for $500. For flash memory, you will have to add a couple of zeros.”
There is also the problem of capacity. “The highest density flash memory chips are in the 4-GB area, with 8 GB coming on line,” said Jones.
Price has been a function, not just of the lack of critical mass in the marketplace, but of the physics of the device, noted Drossel. “This makes them much more expensive to manufacture relative to magnetic media disk drives,” he said.
CONSUMER-DRIVEN SAVINGS
The good news is that prices have been coming down, which has increased the opportunities for deploying SSDs to greater numbers of military computing applications. Price reductions were driven by the consumer market, according to Drossel. When flash memory made its appearance in digital cameras and MP3 players, companies made a mad dash to grab a piece of the action. As a result, the price of a gigabyte of SSD capacity has fallen an average of 15–20 percent per year in recent years, and that trend is likely to continue for some time, Drossel said.
“The continued decrease of prices for higher capacity solid state storage has made it all the more appropriate medium for military applications,” said Francisco Fronda, assistant vice president for product management at Bitmicro Networks, a maker of solid state storage media. “Coupled with the advantages of ruggedness and lower power consumption that it has over other storage technology solutions, such as magnetic hard drives, these will strengthen the rationale for its use in the military market and should pave the way for even wider adoption. We can see numerous manufacturers today joining the SSD bandwagon as new players emerge from stealth mode, all developing new products that will address the growing needs of the military and industrial applications segments of the market.”
“SSDs are primarily used in military grade notebooks and tablets that are used by field personnel as well as installed in military vehicles,” added Winslow. “As the costs for these systems decrease, the breadth of the military deployment will increase.”
Solid state drives are already providing significant opportunities for military equipment manufacturers to decrease costs and increase the performance and reliability of their products, according to Winslow. “Intel had one military OEM customer tell us they are saving around $1,000 per notebook PC and tablet by not having to shock-proof their existing hard disk drive bay,” he said.
Earlier this year, Phoenix International Systems introduced a data storage plug-in blade in which one or two SSDs are used. The VS1-250-SSD Serial Attached SCSI (SAS)/Serial ATA (SATA) based Solid State Disk VME, which houses one or two 2.5-inch SAS or SATA SSDs and up to 256 GB of storage per device, is designed as a drop-in replacement for a traditional hard disk drive that is configurable for the environment in which it is to be operating, according to Deacon.
SAS and SATA refer to available serial disk drive interfaces. SAS is considered to be the more sophisticated of the two, since it provides multiple paths to data, thus mitigating the possibility of failure.
The VS1-250 has an operating temperature range from -40 to 85 degrees C and functions at altitudes of 80,000 feet and higher. The VS1-250-SSD also complies with current Department of Defense security standards providing multiple levels of secure erase techniques. The device offers significantly lower power consumption, according to Deacon, and eliminates seek time, latency and other electro-mechanical delays commonly associated with conventional rotating media.
“What our product does allow you to do is pick the type of environment the application is going to work in and then configure product with the characteristics, whether that be protection against temperature, shock, vibration or altitude, tailored for that particular application,” said Deacon.
SPECIALIZED FEATURES
Price was never the key factor in employing SSDs in missioncritical military systems that required the ultimate in reliability and/ or needed to withstand extreme environmental conditions, according to Drossel. “Now that prices have come down for SSD capacity, that technology is now a lot more attractive for applications such as mapping, high-end graphics, and data radio traffic. As SSDs with capacities of 120 GB have been introduced, and with a 250-GB drive coming soon, you will see them appear where they were never considered before, in applications like notebook computers and notebooks that provide portable computing in the field.”
For Fronda, the traditional use cases will continue to be the driving force in military applications such as satellites and UAVs. “With SSDs becoming less expensive these days,” he said, “UAV data acquisition applications will stand to benefit from lower flight times and costs to perform the same mission because of higher SSD capacities.”
In view of continuous price reductions and stiffer competition, specialized makers of SSDs are differentiating themselves from the competition by developing and shipping products with specialized features, including the introduction of full-disk encrypted SSDs. “Through the use of encryption, users who do not have the encryption keys will not be able to access data on the SSD,” Fronda explained. “Other features that are being developed are antivirus and antimalware agents being incorporated in the SSD. This adds another layer of security preventing the corruption of data.”
SSD-makers are also including mechanisms that allow for very rapid and secure erasure of data. “These devices can erase all of the data residing on every memory chip in one simultaneous action,” said Fronda. “SSD-makers are also consistently developing algorithms to nondestructively erase the data at the fastest possible time.” Adding additional security to disks opens them up to a host of new applications. Jones sees custom SSDs making their way to GPS applications, with their many security requirements.
“In the future, especially as the size of these devices gets smaller, SSDs are going to be used, not only on large weapons systems such as aircraft, but by frontline troops using man-held devices,” said Deacon. “You can have a Global Hawk at 80,000 feet that sees a threat to the ground troops in the area. That threat can be communicated via a satellite data link directly to these frontline troops so that they get that intelligence in real time. To allow that to happen, you need to provide some capacity for data storage on those man-held systems.
“A lot of these devices allow the storage of communications, imagery and intelligence data that can be very sensitive,” Deacon continued. “They include encryption routines that encode the information, but even with encryption it is possible to break codes. Incorporating flash SSDs into the applications infantry troops carried out to the front line makes the data more secure because the data can be destroyed if the devices fall into enemy hands.”
ADVANCED MATERIALS
Fronda has also seen SSD devices being fashioned from more advanced materials. “In terms of reliability, we are seeing the development of new enclosures made from new materials that are more rugged to protect the drive from harsh physical environments,” he said. “For the components, we see the development of radiationhardened components and alternative memory components that are less prone to data integrity problems.”
Deacon predicted that continued increases in capacity and falling prices will allow SSDs to “take over more and more business from traditional rotating media.”
“If we could get the cost of SSDs down to the price of rotating media, we would replace all of them,” said Jones.
“We are now doubling the density of SSDs in less than 18 months,” Drossel added. “I don’t know if we will ever reach density of magnetic drives at an applicable cost, but it is clear that we are making great strides in that direction. The marketplace, and especially the military market, is not driven only by dollars per gigabyte.”
“The military market, being a traditional one for rugged storage, will continue to provide a solid base of revenue for the SSD market,” said Fronda. “It leverages the advantages inherent in SSDs that are not normally provided by other storage technology solutions.” But the enterprise market for SSDs is growing and is much more price sensitive than the military market. Therein lies a potential pitfall for the military, according to Jones.
“As prices continue to fall, the enterprise market will be taking off,” he said. “Larger companies are buying out smaller in order to get into the enterprise market, and the end result will be that a lot of military suppliers of SSDs will be chasing enterprise customers.
“The enterprise market is not as demanding in its requirements for solid state media as is the military, in terms of endurance, security, small geometrics and increased capacities,” Jones said. “The downside of this is that performance of flash drives might degrade as a result, and that doesn’t help the military.” ♦