The 3480, announced in 1984, was a major milestone for IBM storage. "Everything about this product is new," said Al Rizzi, tape products manager in the Tucson lab. Two radically new features were shape and size: square tape cartridges replaced the traditional round reels and the overall footprint of the box was reduced. Plus, data storage density and speed improved.
Previously, the industry standard had been a 10.5-inch round tape reel that stored 160MB of data and had an uncompressed data rate of 1.25MB per second. The new 3480 used a 5.5-inch square cartridge, stored up to 200MB of data and executed at the rate of 3MB/second. Additionally, the 3480 Magnetic Tape Subsystem required less than half the floor space of an equivalent installation of 3420 magnetic tape units from just a decade earlier.
Technological breakthroughs with 3480:
"The 3480 is the result of thoughtful, customer-oriented design goals," said Andy Hopper, tape library product planning manager at the time. "We practically lived with customers to look at how they use storage products. This product is what the customer wants."
A series of enhancements and firsts for tape storage quickly followed the 3480. Improved Data Recording Capability (IDRC), introduced in 1986, provided a significant advancement in data compression for tape. The ESCON (Enterprise Systems Connection architecture) channel interface, delivered in 1987, enabled tape storage across several kilometers -- a distance previously unheard of.
The 3480 product family was further extended by the 36-track 3490E drive and a new extended-length chromium dioxide tape in 1991. The 3490E provided 800MB of storage in the same cartridge format as the earlier 3480. With IDRC, the capacity of the 3490E was expanded to over 2.4GB, the highest data capacity available at that time.
A significant increase in the embedded control function (microcode) enabled the 3480 to optimize the operation, reliability, performance and maintenance of tape storage. Tape-control microcode had become a critical component of high-speed, high-reliability tape as well as disk storage. Lessons learned with one helped to improve the other.