Model: iStorage diskAshur PRO2 2TB USB 3.1 Encrypted Portable Hard Drive
Manufacturer: iStorage
Provided By: iStorage

iStorage is the trusted global leader of award-winning, PIN authenticated, hardware encrypted portable data storage devices. Founded in London, England in 2009, the company has become recognized as a leading innovator and supplier of ultra-secure, easy to use and affordable portable data storage devices. Today, iStorage offers a wide range of innovative products including USB flash, hard disk and solid-state drives capable of storing and protecting data to military specified encryption levels while ensuring compliance to regulations and directives.

One of the latest additions to iStorage's product lineup is the diskAshur PRO2 portable hard drive. According to the company, the diskAshur PRO2 is the world's first and only portable hard drive that is NCSC CPA, FIPS 140-2 Level 2/3, NLNCSA BSPA and NATO restricted level certified. It features iStorage's Enhanced Dual Generating Encryption (EDGE) technology which includes a built-in FIPS PUB 197 validated AES-XTS 256-bit hardware encryption engine as well as a dedicated on-board Common Criteria EAL4+ ready secure microprocessor to enhance security through true random number generation and built-in cryptography. While this all may sound complicated, the diskAshur PRO2 is easy to use. Simply connect the integrated cable to any device with a USB port and enter your PIN to access your data.

The diskAshur PRO2 portable hard drive is available in capacities ranging from 500GB up to 5TB. For this review, iStorage sent us the 2TB version of the drive which is capable of delivering up to 148 MB/s sequential read and 140 MB/s sequential write speeds.

With specs and features like this, it's hard not to be impressed by the diskAshur PRO2. However, as you all know by now, we're not ones to take things at face value. In this review, we'll take a closer look at iStorage's encrypted portable hard drive and then put it through its paces to see how well it performs. Does the diskAshur PRO2 have what it takes? Keep reading as we find out.

Packaging and Contents:

The diskAshur PRO2 comes in a small, black and blue box. Along with a picture of the drive, the front advertises key features like its 2TB capacity, PIN authentication, military grade encryption, USB 3.1 connection and support for iStorage's EDGE technology. The back of the box provides a bit more information regarding the diskAshur PRO2's features in a number of different languages.

Inside the box, you'll find the diskAshur PRO2, a carrying case, quick start guide, warranty information and a sheet of paper with information on where you can download the included backup and antivirus software.

Physical Features:

The diskAshur PRO2 measures 124 x 84 x 20 mm and tips the scales at 225g when equipped with a 2TB hard drive. While this is a bit on the large side for a portable hard drive, its hardware encryption engine, physical protection mechanisms and keypad account for most of the extra bulk and weight.


The diskAshur PRO2 is also equipped with an integrated USB 3.1 cable that tucks into the side of the drive. The downside here is that it is pretty short. This probably won't be an issue if you're using the diskAshur PRO2 with your laptop or mobile device but you'll probably want to buy an extension cable if you're going to use it with a desktop computer.

With the diskAshur PRO2's components being completely covered by a layer of super tough epoxy resin, I wasn't able to crack it open. However, using CrystalDiskInfo, I was able to see what hard drive was in the enclosure. Looking at the screenshot below, you can see that iStorage has used Seagate's 2TB Mobile HDD (ST2000LM007). This drive features a SATA 6.0Gb/s interface, 128MB cache and a 5400 RPM rotation speed.

The diskAshur PRO2 has been designed to be easy to use. The drive is compatible with all operating systems and can be set up and operated without any sort of software. Everything is done using the keypad and the LED indicators on the top of the device.

When you plug the diskAshur PRO2 in, it undergoes a rapid self-test to verify all security components are working properly. The LEDs will go through 3 test stages, blinking in sequence red, green and blue, followed by two green blinks and then to red (Standby State) on a successful test.

The diskAshur PRO2 can be unlocked with either an Admin PIN or, if you have one set, an independent User PIN. Once unlocked, the green LED will remain on and in a solid state. The drive will automatically lock after a pre-determined amount of time. Otherwise, it can be locked down immediately by pressing the ‘LOCK’ button.

The diskAshur PRO2 can also be put into "Admin Mode." From here, you can change the Admin PIN, add a new User PIN, set the minimum PIN length, enable read-only mode, change the auto-lock clock and even set a self-destruct PIN. When used, the self-destruct feature deletes all data, as well as any Admin/User PINs, and then unlocks the drive. The diskAshur PRO2 will then need to be partitioned and formatted before any new data can be added to the drive.

To keep people from guessing your PIN, the diskAshur PRO2 utilizes a brute force hack defense mechanism. If an incorrect PIN is entered 15 (3 x 5 PIN clusters) consecutive times, then all Admin/User PINs, the encryption key and all data will be deleted and lost forever. The diskAshur PRO2 will then need to be formatted and partitioned before it can be reused.

The test system used in this review is equipped with an Intel Core i7-6700K CPU, GIGABYTE GA-Z170X-UD3 motherboard, 32GB (16GB x 2) of Crucial Ballistix Sport LT DDR4 memory, Samsung 960 PRO 512GB SSD and a GIGABYTE GeForce GTX 1060 WINDFORCE OC 6G graphics card. For the operating system, I installed a fresh copy of Windows 10 Enterprise.

To test the performance of the iStorage diskAshur PRO2, I ran a series of benchmarks using CrystalDiskMark, HD Tach RW, ATTO Disk Benchmark and HD Tune Pro. To get a feel for the "real world" performance, I also copied and pasted 1GB of random files and directories as well as a single 4GB ISO file in Windows Explorer.

CrystalDiskMark 5.1.2:

First, I ran a few quick tests using CrystalDiskMark. This benchmark tool measures the performance of a storage device by testing its sequential read and write speeds as well as its random read and write speeds using blocks 512K and 4K in size.

iStorage diskAshur PRO2 - USB 3.1
iStorage diskAshur PRO2 - USB 2.0

According to iStorage, the diskAshur PRO2 is capable of reading at 148 MB/s and writing at 140 MB/s when connected to a USB 3.1 port. While the drive performed well, it came up a bit short of these numbers in CrystalDiskMark's sequential read and write speed tests.

HD Tach RW

Next, I used HD Tach to test the diskAshur PRO2's read, write and burst speeds as well as its seek times and CPU usage.

When connected to the computer's USB 3.1 port, the diskAshur PRO2 had average read and write speeds of 105.7 MB/s and 105.4 MB/s, respectively, as well as a burst speed of 184.1 MB/s. The drive wasn't nearly as fast when using USB 2.0 though. Compared to what we saw with USB 3.1, the diskAshur PRO2's average read and write speeds dropped by more than 68 MB/s.

ATTO Disk Benchmark 2.46:

I also used ATTO Disk Benchmark to test the diskAshur PRO2's sequential read and write speeds. The test was run using blocks ranging in size from 0.5KB to 8192KB and the total length set to 256MB.

iStorage diskAshur PRO2 - USB 3.1
iStorage diskAshur PRO2 - USB 2.0

The diskAshur PRO2's read speeds topped out at about 133 MB/s and its write speeds at 139 MB/s when connected using USB 3.1.

HD Tune Pro 5.00:

Next, I ran a series of tests using HD Tune Pro. This hard disk utility measures a drive's performance by testing its sequential read and write speeds as well as its access time, burst rate and CPU usage. For this review, I used it to benchmark the diskAshur PRO2's random read and write speeds, random access times and the number of operations per second.

Read Benchmark - USB 3.1
Read Benchmark - USB 2.0

Write Benchmark - USB 3.1
Write Benchmark - USB 2.0

Once again, the diskAshur PRO2 performed fairly well when connected to the computer's USB 3.1 port. The drive had average read and write speeds of 103.4 MB/s and 98.9 MB/s, respectively, and a burst rate of 224.5 MB/s when reading.

Random Access Read - USB 3.1
Random Access Read - USB 2.0

Random Access Write - USB 3.1
Random Access Write - USB 2.0

Using USB 3.1 didn't have nearly as big of an effect on the diskAshur PRO2's random read and write performance. Nevertheless, the IOPS and average speeds were, in most cases, higher than what we saw when the drive was connected to a USB 2.0 port.

"Real World" Benchmark:

To test the "real world" performance of iStorage's diskAshur PRO2 hard drive, I copied and pasted 1GB worth of randomly generated files and directories. All of the files are between 1KB and 95MB in size and no more than five directories deep. To see how well the drive handled large files, I also copied and pasted a 4GB ISO file.

   1GB of Files 4GB ISO File
Write: 23 seconds 33 seconds
Read: 10 seconds 32 seconds

The diskAshur PRO2 performed fairly well here, taking 23 seconds to write 1GB worth of test data and 10 seconds to read it back.

Final Thoughts:

The diskAshur PRO2 is a great choice for the security conscious professional looking for an ultra-secure, yet easy to use, portable hard drive. In addition to its stylish, tamper proof design, the diskAshur PRO2 offers real-time military grade AES-XTS 256-bit full disk hardware encryption. The drive also utilizes a dedicated on-board Common Criteria EAL4+ ready secure microprocessor to protect itself from any external tampering, bypass laser attacks and fault injections. Despite its many layers of security, the diskAshur PRO2 is very easy to use. Simply plug it into a USB port, enter your PIN on the keypad, and you have access to your data.

When it comes to performance, the diskAshur PRO2 did relatively well in our tests. With all of the encryption being done at the hardware level, we found it to be just as fast as a non-encrypted hard drive. Thanks to its USB 3.1 interface, the diskAshur PRO2 was able to read at 134 MB/s and write at speeds as high as 139 MB/s. The drive is also backwards compatible with USB 2.0. However, as you saw in our tests, it's much slower when operating in this mode.

The diskAshur PRO2 portable hard drive is available now in capacities ranging from 500GB up to 5TB. Prices on currently range from $222 up to $451, with the 2TB version reviewed here retailing for about $313.


  • Available in 500GB, 1TB, 2TB, 3TB, 4TB and 5TB capacities
  • NCSC CPA, FIPS 140-2 Level 2/3, NLNCSA BSPA and NATO restricted level certified
  • Real-time military grade AES-XTS 256-bit full disk hardware encryption
  • Common Criteria EAL4+ ready on-board secure microprocessor
  • PIN authentication with easy-to-use keypad
  • USB 3.1 Gen 1 interface
  • Good looking, tamper proof design
  • Brute force hack defense mechanism
  • Self-destruct feature
  • OS and platform independent
  • 2 year warranty


  • Slightly larger and heavier than non-encrypted hard drives
  • Short USB 3.1 cable
  • Pricey