Get It On Tape--Again!

This article is the second in a two-part series. The first part appeared in the April issue of CTR.

For the small to mid-range server market, DDS solutions have been traditionally selected. The 4mm tape drives are excellent backup solutions for workgroups and servers, although they are much slower than today's DLT tapes. Current generation DDS4 technology provide 20GB native capacity with up to 2.4MB/sec data transfer rates. Hardware technology is much improved with active head cleaning capability and enhanced reliability features.

OnStream's ADR (Advanced Digital Recording) technology offers impressive cost, speed, and reliability breakthroughs for the midrange server market. Eight-channel head technology allows low tape speed and continuously variable native recording rates from .5MB/sec to 2MB/sec, allowing ADR drives to match the host's data rate. Throughputs are increased because tape "backhitching" is minimized. Spatially distributed error correction (cross channel) allows exceptional reliability with error rates in the 1 X 10 EE-19 range. OnStream drives are priced well below DDS solutions and support cartridge capacities from 30GB to 65GB compressed.

Mid To High-End Server Backup

Priced below DLT, but above DDS, high-end 8mm tape systems compete head-to-head with DLT. With storage densities equal to DLT and sustained transfer rates of 6MB/sec, AIT technology is gaining a strong following. The AIT drives solved 8mm reliability problems with an improved tape-to-head interface and by using hard-costed, binderless media that minimizes tape wear.

AIT has attracted a strong following because of its unique MIC (Memory In Cassette), which consists of a 16KB memory chip in the data cartridge. The drive stores and retrieves drive and user-generated information directly from the chip, providing much faster data access. The drive also monitors head output for contamination and will automatically activate the built-in active head cleaner when it is required. Overall, the drive is an excellent solution for high-performance backup.

Similar to the AIT drive, Exabyte's Mammoth 2 drives use 8mm media and tapes with a patented head cleaner built in. While they don't use. MIC, Mammoth technology provides fast and reliable operation up to 12MB/sec native and offers extensive automation support for multi-terabyte applications.

QIC Still Evolving

Tandberg continues pushing the technology envelope for belt driven cartridge drives with their SLR (Scalable Linear Recording) technology, which improves the density and performance of the drives while maintaining impressive backward compatibility to several generations of media. With a native capacity of 50GB and up to 5MB/sec transfer rate, the SLR drives are designed for high duty cycle applications. Less expensive than DLT drives, SLR drives offer impressive MBTF ratings and reliable operation at up to 36GB/hr transfer rates.

Growing Automated Tape Market

According to Robert Amatruda, senior research analyst with IDC's Tape and Removable Storage Research Program, the explosive growth of digital content in most organizations is driving the need for more tape storage capacity--beyond that of a single tape drive and a single tape cartridge. IDC expects revenues and shipments in the worldwide tape automation market to accelerate at a compound annual growth rate of more than 25% through 2003. At that time, worldwide shipments of tape libraries, autoloaders, and stackers will total 350,500 and be worth well over $5 billion--more than double the size of the 1999 market.

Libraries contain multiple high performance drives and deliver scalability, making them well suited to SAN (Storage Area Network) and NAS (Network Attached Storage) applications. Autoloaders and stackers, on the other hand, contain a single drive with five to fifteen slots. They are usually configured to use a tape a day, so that support people only have to change tape magazines on a weekly basis.

Organizations spend thousands of dollars purchasing computer hardware that is really only used to automate the storage, retrieval, and manipulation of what is really important--data. Hardware can easily be replaced and is usually covered by insurance. Lost data is often irreplaceable and, at the very least, extremely expensive to replace manually. With the array of product types, performance specifications, and price points available, tape continues to be the solution of choice for protecting vital data.

Mark Rogers is the tape business unit manager at Verbatim Corporation (Charlotte, NC).