Interoperability: Little Known Facts Part II
The Other Specs: An SSD Is More Than Its Throughput
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What’s needed, then, for dependable encryption is third-party validation. Here the gold standard is the National Institute of Standards and Technology’s (NIST) FIPS 140-2 certification. FIPS validation is rigorous and thorough; it’s not an overnight process, and anything that has a NIST FIPS 140-2 certification has been through the wringer. The encryption keys are deemed protected and properly managed. Seagate’s self-encrypting HDDs and the company’s self-encrypting Pulsar.2 SSDs are examples of storage drives that have received NIST FIPS 140-2 validation.
But how does something like NIST FIPS 140-2 relate to interoperability? Let’s take a data center with a variety of drives as an example. Encryption key management is going to vary from drive to drive, which can put data at risk. Seagate’s self-encrypting drives found in big enterprise data centers rely on IBM’s Tivoli Key Lifecycle Manager. The drives have been subjected to years of validation (both internal and in the field) and have proven effective at encryption. The same can’t be said for other drives, and in the enterprise, that’s playing with fire. Any seasoned sysadmin can supply you with a story or two about encryption incompatibilities, whether it’s driver-related, how an OS deals with device instruction codes, or other matters.
Seagate engineer Jeff Nowitzke helps explains an interoperability conundrum. “With some vendors, you could get into problems with things like how they adjust their PHY settings,” he says. “It’s possible to have low-level, interface-type issues by having multiple vendors. You have high-frequency signals for transfers on your SAS and SATA interfaces, so having the same vendor with similar design centers architecting those signals matters. We’re pretty consistent in how we set up our transceivers for those signaling scenarios, whereas if you have different vendors, you could end up where everything is running fine with one vendor, you change vendors, and all of a sudden it doesn’t work because there’s a marginal issue with your backplane or your system that now comes to light. The storage devices may meet the standards, but doesn’t mean you’re immune from stumbling into margin issues with your system.”
A comparison of SATA (top) and SAS (bottom) interfaces.
Feature compatibility is another way you can be stung if you don’t fully explore a drive’s interoperability. SAS and SATA plugs illustrate this at the most basic level: They are plug-compatible but not even close to being feature-compatible. Manufacturers will frequently produce SATA-based drives exclusively and then turn to a third party to provide a SATA-to-SAS bridge. The bridge could be external, or it could be built into the drive, but that’s not really the point. When a drive uses a bridge, you could get one true SAS port and one port that’s a SATA failover. As a result, those drives will short-change you when it comes to delivering the full buffet of SAS features. A drive like this might not let you format at different sector sizes. Another could severely limit your SMART reporting options. Businesses with limited staff and budgets simply can’t afford to deal with problems that arise from these inconsistencies.
There isn’t an IT buyer on the planet who wants to take the blame when incompatibilities wreak havoc on the data center, so what’s the solution? Of all the storage vendors that have come and gone over the last 30 years, only two or three still exist that offer product lines based on instruction code sets that have been implemented across every application space and in every business environment. So when a company takes the hardened code set baked into their hard drives and ports that into its built-from-the-ground-up family of SSDs, there’s peace of mind in knowing that these new, fast SSDs will seamlessly integrate into existing operations. The cherry on top is when the same company has a history of providing support and helping customers incorporate new storage solutions into their existing infrastructure.