Adrian Briscoe, general manager of Kroll Ontrack
Companies wanting to ensure their data is recoverable from solid state disk (SSD) drives should make sure they use third-party encryption tools with known keys rather than relying on devices’ built-in encryption, a data-recovery specialist has advised.
Noting that the shift from mechanical hard drives to flash RAM-based solid state disk (SSD) drives had increased the complexity of data recovery, Adrian Briscoe, general manager of data-recovery specialist Kroll Ontrack, told CSO Australia that the growing use of SSD in business servers, mobile phones, tablets, laptops and even cloud data centres had made recovering data from the devices “a very black or white situation”.
“You either get everything or you don’t get everything at all” from damaged SSD-based equipment, he explained.
“With mechanical hard drives it’s a percentage situation, particularly since large drives are typically not used to capacity. But with SSDs we spend a lot of time trying to find ways of recovering data. The major issue is interacting with the [SSD controller] chips: Although there are only six controller chip makers, there are at least 220 manufacturers of SSD devices, and the way they’re designed is different from one device to the next.”
Many manufacturers, in particular, had taken their own approaches to data security, automatically scrambling the information on SSDs with encryption keys that are stored on the device itself.
That has presented new challenges for the company’s data-recovery engineers, who work from a dedicated data-recovery clean-room in Brisbane where damaged hard drives are regularly rebuilt to the point where their data can be recovered.
The proportion of SSD and flash RAM media going to that cleanroom had grown steadily, from 2.1 per cent of all data recovery jobs in late 2008 to 6.41 per cent of jobs in Q4 2012.
Recovering data from SSDs is already more difficult than sequential-write hard drives because SSD-stored data is distributed throughout the flash RAM cells by design. Once SSD-stored keys are made inaccessible by damage to the device, however, recovering the data becomes far more complicated – and chances of getting any of it back plummet.
“SSD devices do have encryption on them, and we are recommending people not use hardware encryption on an SSD if they are wanting to ever recover data from that device,” Briscoe explained, suggesting that users instead run computer-based software like the open-source TrueCrypt, whose keys can be managed by the user rather than internally by the drive itself.
“By having encryption turned on, an SSD with a hardware key is going to fail any data recovery effort,” he continued. “We are not hackers, and we can’t get into encrypted data. Instead, we’re recommending that people use something that holds the key outside the device.”
Many users had yet to appreciate the complexity that SSD poses, with a November 2012 customer survey suggesting just 31 per cent were aware of the complexity of SSD-based encryption and 48% saying there was no additional risk posed by using SSDs. An additional 38 per cent said they didn’t know.
The SSD challenge isn’t limited to smartphone-wielding users, however: as data-centre operators increasingly turn to SSD to boost the effective speed of their data-storage operations, Briscoe warned that a growing number of the company’s recovery operations were involving data lost to cloud-computing operators.
“A lot of vendors are using hybrid solutions with a bank of SSDs in a storage area network, then write data to [conventional] drives,” he said.
“We’re seeing more and more instances of cloud providers losing data: they rely very much on snapshots, and if something happens to the data – if there is corruption to the operating system or some type of user error – we are having more and more cloud providers coming to us with data loss.”