Introduction

iStorage is a British company that launched in 2009 after the founder saw a market for encrypted storage, and we saw an example of this last year with the diskAshur M² family of encrypted portable storage that employed an M.2 SATA SSD for a balance of speed, affordability, and of course data privacy. The diskAshur M2 is in itself not a novel idea, with many such products from other companies also having been covered on TechPowerUp. However, they all had one thing in common: The storage was part of the device, and anyone needing multiple drives would have an expensive bill to pay. iStorage clearly agreed, and thus came about the new datAshur SD. Thanks go to iStorage for arranging a review sample for TechPowerUp.


The solution seems obvious enough—decouple the encrypted storage from the hardware decryption key itself. The keypad-based form factor is clearly successful in its own right, allowing end users to program an alphanumeric key of their choice that is stored on the device large enough to host the processor and a small power source. So if M.2 SSDs were not an option, why not try memory cards? This is what the "SD" in the datAshur SD does, with encrypted microSD cards providing the necessary storage solutions. This way, users are able to purchase the drives for decryption at a lower cost. Let's now see how this works out in practice courtesy a twin pack of the drives and a microSD card iStorage provided.

Packaging & Accessories

The datAshur SD is meant for those who want to use a single source of storage on multiple devices, each with an associated drive. It's quite niche an application no doubt, but I can already think of several IT managers who'd salivate at this prospect should the drives be cloneable for the encryption keys. As such, a twin pack is the minimum that makes logical sense for the datAshur SD, which is what we have here. It ships in a similarly designed cardboard box designed to the iStorage diskAshur M² we saw before, employing a predominantly blue color scheme. On the front is the company logo and product name, along with a render of the product and unique selling point. More information is provided on the back, which also confirms that the datAshur SD only works with iStorage encrypted microSD cards. Two security seals on either side keep the contents in place on their way to you.


Open the outer box on either end and you can now pull out the inner box that is another piece of thick cardboard with the two drives inside machined cutouts in a thick foam sheet. Each has the same warning about the use of microSD cards. Another cutout on the side holds two USB Type-C to Type-A adapters for when you don't have an available Type-C USB port on your PC, which is a clear indication that these are Type-C USB flash drives. Underneath this top layer is where we find relevant paperwork, including a multi-language quick start guide that walks you through the setup and use of the drive (online copy here). There is a more detailed user manual too, as well as another which goes over the supporting software program found here. The twin pack of the datAshur SD comes with a free license of this software program, further sweetening the deal over two single packs if you were so inclined. There is thus a card reminding you to register the device, with the license key and pin for the software on the other side of the card.

Closer Look & Performance Testing

The datAshur SD follows the same design language as the iStorage diskAshur M², employing an extruded aluminium cover given a durable and rugged anodized blue finish. Indeed, iStorage says it can withstand the weight of a 2.7 ton vehicle rolling over it, as well as a 4 m drop onto hard concrete. There is a protective cover over the actual drive, with a rubber gasket seal at the opening for IP68 dust and spill resistance. This outer cover has the product name etched into it, and there is an integrated keychain ring on the side that opens up.


The drive housing is made out of the same hard anodized extruded aluminium, and on the back we see certification information along with confirmation of the use of a 3.7 V Li-ion battery inside. I like the angular form factor cut into the otherwise rectangular cuboid drive, including on both sides with either the keychain ring or USB Type-C connector. Three LEDs near the connector shine red, green, or blue respectively and are used as visual indicators for the various operating states of the drive. Below, occupying the majority of the surface there, is the keypad that allows for on-device encryption and decryption. The keypad comes with a polymer coating that performs double duty, preventing key wear and hiding key usage to keep anyone from finding the commonly used keys. Disassembly is non-trivial, but iStorage tells us an epoxy coating is inside, in addition to thermal heat transfer considerations for the SD card reader and controller, and a Common Criteria EAL5+ (Hardware Certified) secure microprocessor. It is on the side that we see the cutout for the microSD card.


This is the opportune time to bring up the iStorage encrypted microSD cards thus, which I already know will cause a few questions about whether this is not simply a move to get people to purchase more expensive SD cards rather than use their own. Indeed, these memory cards can only be used with the datAshur SD at this time while still retaining data; they come with a firmware allowing data to be written onto them using FIPS PUB 197 validated, AES-XTS 256-bit hardware encryption. I was sent a 1 TB microSD card, which ships in frustrating packaging that requires you to tear it apart to access the plastic clamshell it comes inside. The plastic case is very handy for when the memory card is passed along to users with a compatible datAshur SD drive, and the branding on the memory card makes what it's for clear. If you use this microSD card on another device, such as a generic card reader, camera, or phone, you will have to format the drive to access it, meaning the encrypted content on it is lost.


Setting up the datAshur SD is simple enough and begins with inserting the microSD card into the slot of any one drive. This will be your default master drive thus, with other drives secondary units that can be cloned. The provided Type-C to Type-A adapter can be handy for many no doubt, especially based on my memories of underfunded IT departments that have to make do with old PC hardware. I won't bore you with all the details of the rest of the process since it's identical to what we saw on the diskAshur M², and the provided quick start guide does a great job of walking you through it. Note that you do not need to have the drive plugged into a USB port to do all this since the internal rechargeable battery has enough juice to initiate admin mode, set up the encryption key consisting of a minimum of eight digits, save it to the device, and start it up. The three LEDs come in handy since everything is done onboard the device without any software drivers, and you will have to format the drive the first time to set up the storage volume itself. The rest of the functionality is extremely detailed, including the option to create user pins and profiles, recovery pins, set the drive to read-only mode, enable auto-lock after a preset amount of time, configure the brute hack defense mechanism in terms of how many failed attempts are allowed before certain actions have to be taken, do a complete reset, and, my personal favorite, set a self-destruct pin that can be used to erase all stored content in pressing times, including encryption keys.


The reason behind iStorage's patented Key Writer software program is simple enough. I'll go back to the IT manager example, and consider there being a small team of ~10 people that need to have temporary access to sensitive data. In that case, you would have the master drive and nine other datAshur drives for the users. Registering for the software with the license and pin included with the twin pack is simple, with the program quite lightweight when it comes to system resources. The first step is to set your drive as the master drive as seen above.


The help section shows the various cloning options, which is what this program is really for. You would have the encryption key known to you, and then clone the security settings onto the other drives, with up to nine other drives cloned simultaneously. This can be done on a daily basis if you are so inclined, and there is an automatic logger to keep track of when what was done. This way, others can access the data on the drive easily enough without changing the decryption key themselves each time. It's certainly a niche application, especially since there remains a single microSD card in this example. Of course, nothing is stopping you from purchasing more memory cards and going back and forth between them, but at that point, you might as well invest in a cloud-based secure storage platform instead.


Given the use case here, actual drive performance is not as critical as reliability. As such, I wasn't too surprised to see sustained read and write speeds maxing out at 100 Mbps, which makes these drives plenty fine for USB 3.2 Gen 1 (USB 3.0) ports—no need to worry about needing USB 3.2 Gen 2/2x2 ports for making the most of them. At the same time, I am left wanting more since the point is to also share the memory cards around, whereby faster transfer speeds would be handy, especially for random file sizes.

The iStorage DatAshur SD is an extremely recent release, so much so that I haven't seen it in stock for sale outside of the iStorage store in the UK yet. You make use of this modular system by purchasing the drives and microSD cards separately, with iStorage having free 30-day evaluation trials as well as custom engraving options. All drives come with a three-year warranty and free lifetime technical support, and the drives support MS Windows, macOS, Linux, Chrome, Android, Thin Clients, Zero Clients, Embedded Systems, Citrix, and VMware. The functionality of it is beyond reproach, with everything here shared with the equally capable diskAshur M² we saw before.

You can purchase single drives for £69, or a twin-pack with a free KeyWriter license for £138, and the microSD cards are available in 32, 64, 128, 256, and 512 GB, as well as 1 TB, with prices ranging from £25 to £300 including VAT in the UK. Pricing in other regions should be equivalent, if not better in the US as with some other iStorage products. This means the microSD cards are certainly more expensive than standard contemporaries, including those capable of faster transfer speeds, but the drives themselves cost significantly less than equivalent encrypted portable storage once you cross a threshold in terms of either their needed number or total storage, or a combination of both. This makes the datAshur SD more attractive with volume sales than for individuals or smaller teams, which also explains the available volume sale discounts and customization options.