by Mark Brownstein
In early May, a number of significant announcements were made, effecting the future of RDX. In this article, I’ll take a look at RDX and explore the impact of the latest announcements.
What is RDX?
RDX is a technology standard that defines a cartridge containing a storage medium, and a docking device into which the cartridge attaches. In practical use, the ‘cartridge’ is designed to hold a 2.5” notebook hard drive. A high level of environmental protection is built into the cartridge, providing protection from impact, dust, and other environmental challenges. The cartridges are guaranteed for thousands of insertions and removals from the docking bay and are said to be able to withstand at least ten years of regular use.
The docking device securely connects the inserted cartridge to a SATA connector inside the dock. Logic in both the dock and the cartridge provides a handshake between the devices and also makes it necessary to connect the cartridge to the dock – although it’s physically possible to connect SATA signal and power cables to an RDX cartridge, the drive inside the cartridge won’t work with this type of connection.
RDX is said to offer the best of tape and disk. On the tape side, the cartridge is very robust, easy to insert into and remove from a dock, and can be easily stored or transported. On the disk side, the system provides very robust storage. Because RDX uses disk drives, access to data is fast (random access to drive platters or….(in the recent announcement)), there’s no streaming of tape to a particular location required. The drives in an RDX system are hot swappable – one drive can be removed from a dock and replaced with another, and the computer to which the RDX dock is attached gracefully handles the swap.
RDX drives can be used for backup and recovery. They can be used for data storage. Docking devices are available as single cartridge devices, and docking adapters with as many as 8 (and possibly) more docks are available.
Additionally, docking adapters can be installed inside computers, using a SATA signal and power connection. External versions of RDX docking devices are also available.
The Announcements...
In early May, Tandberg Data made a few announcements that I believe are quite important for the continued success and accelerated adoption of RDX. Tandberg will soon ship a 1.5 terabyte cartridge, which will make the format even more attractive for data protection – as well as basic storage or mobility – than it already is. According to an RDX roadmap provided by Tandberg, capacities of as many as 3 TB are planned for the future. (It should go without saying that the capacity of RDX cartridges relies on the ability of notebook drive makers to continue making larger and larger notebook drives).
One of the two most important advancements announced by Tandberg is the availability of a USB 3 interface for its external docks. This is extremely significant. Previous versions of these devices use USB 2, with a native speed of 480 mb/s. USB 3 is more than 10 times as fast as USB 2, capable of delivering up to 5000 mb/s transfer speeds. What this means is that, in the past, with an RDX cartridge in a USB 2 dock, the bottleneck was nearly always the speed of the USB interface connecting the drive to the computer. With USB 3, connected to a computer with a USB 3 interface, the breathtakingly fast data transfers are probably only being held back by the maximum speed of the drive and the SATA interface to which it’s connected.
(From the standpoint of this recent USB 3 user, the transfer speeds are amazing. I recently transferred a test file to a USB 3 drive in about 13 seconds. The same file, sent over USB 2 took well over a minute to complete. For users who want to move a lot of data, USB 3 is a great addition.)
USB 3 is also compatible with USB 2 on computers. A USB 3 dock will work when connected to a USB 2 hub or computer – performance will still be at USB 2 speed, but the device WILL be compatible. To a cartridge, it doesn’t matter whether it’s connected to a SATA dock or a USB dock – the drive inside the cartridge will be subject to the constraints of the SATA connection between it and the dock.
Although most currently available RDX cartridges only support SATA I (1.5 MB/s) or SATA II (3 MB/s), future drives with SATA III (6 MB/s) performance are being supported. Once SATA III devices and USB 3 docking stations become available, maximum data transfer speeds of the drives should pretty closely match the available speeds of the USB 3 bus. It may be somewhat challenging to find the bottleneck in such a match.
The other significant technology announcement is that Solid State Drives (SSDs) will be available for RDX. This is truly significant, because SSDs bring many advantages to the RDX table. First, they are all solid state – built of Flash memory chips – so there are no moving parts. This also makes the SSDs extremely fast – capable of rapidly moving data over the USB 3 connection or, if in a drive bay inside a computer, over the computer’s SATA cables. Although it may take a long time (if ever) for SSDs to catch up with capacity of 2.5” hard disk drives, the performance advantage to be achieved with SSDs is significant, and should quickly earn SSDs an important place in an organization’s backup and RDX strategies.
Additionally, SSDs are green – their energy use is very low when compared to HDDs. There have been reported negatives related to SSDs (issues such as limited read/write cycles, for example), but manufacturers are working hard to accommodate for or overcome these issues. SSDs will continue to improve.
In addition to the announced availability of SSD and USB 3, Tandberg acquired the RDX development group at ProStor Systems, a company that claims to have developed RDX. The acquisition includes ProStor’s ‘RDX removable disk business…including intellectual property and key members of ProStor’s RDX engineering team,’ according to a ProStor press release. ProStor, which offers large storage systems that are based, in part, on RDX, will continue to be offered their manufactured products.
What it all means
The acquisition underscores Tandberg’s commitment to RDX. It’s assumed that, by consolidating the R&D at Tandberg with the development talent acquired from ProStor, the progress of RDX will accelerate, further cementing Tandberg’s position as one of the leaders in RDX.
As a geek who used to use what were called ‘mobile docks’, to transport data from one computer to another, it’s great to have a compatibility standard. With numerous companies supporting the RDX cartridge and docking specifications, the future of RDX for business – and perhaps even geeks like me – looks increasingly bright.
Mark Brownstein is Executive Editor at WestWorld Productions Inc, publishers of Computer Technology Review
