Storage: back-up on the desktop

The increasing demand for new, more flexible desktop storage is being met in a number of ways. Jane Dudman reports on new...

The increasing demand for new, more flexible desktop storage is being met in a number of ways. Jane Dudman reports on new developments in disc technology

Demand for desktop storage is shooting up, but that need not land companies with huge bills, since the price of storage capacity is coming.down. The simplest type of desktop storage is the PC hard disc drive, the capacity of which has leapt up over the past few years. But disc drives fill up rapidly and do not have the security advantages of removable storage.

The traditional answer has been to back-up either to a tape device or onto a floppy disc, and with the development of CD and DVD, disc capacity has increased enormously.

Tape has been around for a long time. Digital Audio Tape (Dat) was developed at the end of the 1980s, based on helical scan technology, as was the 8mm video tape cartridge from Exabyte, which also proved popular. Recently, there have been a number of different tape storage developments, presenting customers with a great deal of choice, but this has also resulted in a huge and bewildering array of different devices and standards.

The next generation of helical scan tape systems includes technologies such as Sony's 8mm Advanced Intelligent Tape, seen as a possible successor to both Dat and Exabyte.

Linear systems

Meanwhile, linear tape systems are also forging ahead. Data Linear Tape (DLT) systems, in particular, have sold well. This tape technology was initially developed by Digital Equipment Corporation, bought in the early 1990s by storage specialist Quantum, and sold heavily by many major PC and server suppliers. DLT is now competing against the higher-capacity Linear Tape Open (LTO) technology developed by Hewlett-Packard, Seagate and IBM.

Paul Sleep, library product manager of tape storage supplier M4 Data, says, "Tape has become hot, not just because it still provides the capacity per pound that users want, but there is also a lot of confusion in other markets, with all the choice between CD, CDR, DVD, and so on."

One of the major problems in choosing any desktop storage system is trying to second guess both capacity and technical developments. Tape system manufacturers like M4 Data like to point out that developments in disc technologies have resulted in customers having to buy new hardware devices to keep up, rather than simply being able to upgrade their discs.

But the real problem with desktop storage, according to Sleep, is that changes in work patterns are not being taken into account. "The average desktop user tends to have to fend for themselves, which usually means buying some kind of Zip drive, or having to remember to back-up to the company server," he says. "But that won't work with a mobile workforce. They need things on their local disc, but they also need to back up and archive off that information. Having a tape drive by the machine won't work, because the user isn't there half the time."

Low cost options

This increasing demand for new, more flexible desktop storage is being met in a number of ways. New suppliers, such as OnStream and Benchmark, have already brought down the cost of desktop storage systems. OnStream was spun off from Philips in 1998 with the rights to Philips' digital compact cassette system and the goal of bringing down the cost of storage to less than £1 per gigabyte.

Syd Virdi, OnStream's vice president of sales and marketing, says that goal has been achieved with OnStream's low-cost linear drive 30Gbyte digital tape device. One of OnStream's external drives retails at about £220 and cartridges cost less than £30.

While some storage suppliers are moving up to focus on the server and mid-range market with systems like LTO, suppliers like OnStream believe there is a huge opportunity in the desktop market. In January, for instance, Quantum launched its Snap Server range of network-attached storage, aimed at small and medium-sized businesses, with the emphasis on ease of implementation and low cost.

But no matter how much storage costs fall, the real issue remains implementing a system that people will actually use. "Users don't like back-up devices," says Virdi. "Previously, they have been complex and slow."

So as well as improved hardware, a lot of development work has gone into the software that carries out the back-up process. Onstream claims that its Echo software enables 7Gbytes an hour of desktop data to be backed up - so a 20Gbyte disc drive would take three hours. After that, however, only changes to the disc drive would be backed up, taking a much shorter length of time.

"Performance is important," says Virdi. "People don't want to wait when they click on a file, so as well as buying the largest capacity they can find, customers should also check out the performance."

With mobile computing on the rise, backing up data from laptops and remote machines has been a technical challenge for software developers. Microsoft claims that one of the key features in Windows 2000 is the ability to synchronise data from remote machines and back it up automatically. Specialist developers of mobile storage systems include companies like Calluna, which sells the 260Mbyte MoveIT hard disc drive for mobile systems.

Online storage is another option being promoted by companies such as Netstore. This enables users to back up their data to an online secure data store over an Internet connection. Again, though, the issue is about remembering to carry out regular back-ups or implementing the ability to carry out back-ups automatically.

Desktop storage systems

Advanced Intelligent Tape: 8mm tape system developed by Sony to replace Dat/Exabyte, with greater capacity

Data Audio Tape: most ubiquitous tape back-up system on the market. Cost-effective, but limited capacity of 20Gbytes

Data Linear Tape: well-established linear tape system developed by Quantum. Top capacity is 40Gbytes. More suitable for file server back-up

Linear Tape Open: developed by HP, Seagate and IBM. Greater capacity than DLT - aimed at the mid-range market

Exabyte: eponymous 8mm video tape cartridge system from Exabyte

Travan tape drives: aimed at small businesses/home workers. 10Gbyte capacity

VXA: proprietary 8mm helical tape scan drive from start-up Ecrix as higher capacity replacement for Exabyte. Capacity 66Gbytes

Top tips for buyers

  • Try and get some meaningful figures on reliability. Ask your supplier for reference customers to see how the devices work in real-world installations
  • Generally, the bigger the capacity, the lower you'll pay per gigabyte, so it can pay to buy big
  • Check on restore times. Desktop users want to be able to get at their files quickly
  • Developments in storage can end up leaving users behind. Try and ensure there is a forward path, so you can upgrade the media cartridges or discs, rather than have to replace an expensive hardware device

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