New Two-Headed Hard Drive Intended To Secure Web Sites

dlur writes: "This article states that Scarabs (In Japanese), a Japanese company, is developing a hard drive with two heads, one read-only and another that is read/write. With this comes two cables, the read-only side going to the external web server, and the r/w cable going to an internal protected server. While this should make it quite a bit tougher for script kiddies to place their mark on a page, I doubt it will stop any real hackers from getting to a site's DB as that would still need to be r/w."

Comments

More Speed?

[1010011010]

This sounds like a nice drive to use in TiVo-type units as well, so that the read head can return data as the r/w head updates the media, rather than flopping the only head back and forth.

Industry rejected multi-head drives long ago...

[Zinho]

From the article:
"The original idea of a hard disk having two heads emerged around 1985..."

Funny that the technology hasn't been implemented after all this time... Or has it?

From the StorageReview.com reference section:
"Such hard disks have been built. Conner Peripherals, which was an innovator in the hard disk field in the late 1980s and early 1990s (they later went bankrupt and their product line and technology were purchased by Seagate) had a drive model called the Chinook that had two complete head-actuator assemblies: two sets of heads, sliders and arms and two actuators. They also duplicated the control circuitry to allow them to run independently. For its time, this drive was a great performer. But the drive never gained wide acceptance, and the design was dropped. Nobody to my knowledge has tried to repeat the experiment in the last several years.

There are several reasons why it is not practical to make a drive with more than one actuator. Some are technical; for starters, it is very difficult to engineer. Having multiple arms moving around on a platter makes the design complex, especially in small form factors. There are more issues related to thermal expansion and contraction. The heat generated inside the hard drive is increased. The logic required to coordinate and optimize the seeks going on with the two sets of heads requires a great deal of work. And with hard disk designs and materials changing so quickly, this work would have to be re-done fairly often.

However, the biggest reasons why multiple actuators designs aren't practical are related to marketing. The added expense in writing specialty electronics and duplicating most of the internal control components in the drive would make it very expensive, and most people just don't care enough about performance to pay the difference. Hard disks are complex technology that can only be manufactured economically if they are mass-produced, and the market for those who would appreciate the extra actuators isn't large enough to amortize the development costs inherent in these fancy designs. It makes more sense instead to standardize on mass-produced drives with a single actuator stack, and build RAID arrays from these for those who need the added performance. Compare a single 36 GB drive to an array of four 9 GB drives: in effect, the array is a 36 GB drive with four sets of everything. It would in most cases yield performance and reliability superior to a single 36 GB drive with four actuators, and can be made from standard components without special engineering."

So, from the looks of things, it would be easier and cheaper to use single-head drives in easy-to-put-together configurations than put two heads in the same drive. Admittedly, the StorgeReview.com reference's author didn't mention setting up a read-only/read-write scheme, but the logic still works. I'd guess that it would still be easier to make a RAID container that provides read-only access on one channel and read-write on another.

Again, from the article:
"Scarabs is also working on a different version of the technology--instead of putting two heads on a hard disk, the company is connecting two SCSI interface circuits to a conventional hard disk with one head, one set to send read-only electronic signals and the other to send read/write signals."

This company already knows that their gimmick drive won't sell. No one will buy an over-priced drive with higher probability of failure over a (comparatively) cheap SCSI trick that requires no extra moving parts.