Travan
Travan drives are a very simple and robust linear format with single channel recording and a simple tape path. In fact, there are only two moving parts in the drive.
The tape has pre-recorded "servo" patterns at both ends of the tape that the read/write head uses to move into position and correctly align itself to the tape.
Once the head is correctly aligned it locks itself into position. The tape shell is designed to prevent any tape wander, so once the head is positioned for the tape the data channel passes reliably under the heads.
DLT
Digital Linear Tape (DLT) uses special compression algorithm, known as Digital Lempel Ziv 1 (DLZ1), which is utilised to improve data storage quantity and retrieval of data at high speeds.
Inside the DLT drive, data is written on the tape in dozens of linear tracks, usually 128 or 208. Some cartridges can hold in excess of 70GB of data when compression is used.
A variant of DLT technology, called SuperDLT, makes it possible to store upwards of 100GB on a single cartridge and the SuperDLT drive can transfer data at speeds of up to 10MB/s. DLT and SuperDLT technologies are in direct competition with LTO, AIT, and the Mammoth Drive.
AIT
Advanced Intelligent Tape (AIT) uses tapes that measure 8mm across and a helical scanning technique, similar to that used in Mammoth drives.
This technique optimises the data transfer rate and the storage capacity. There are currently three generations of AIT starting at AIT1 that offers 50GB native storage and transfer rates of 4MB/s uncompressed.
AIT utilises a compression algorithm known as Adaptive Lossless Data Compression (ALDC) with a maximum compression ratio of 2.1:1. For details, see www.aittape.com/technology.html.
Mammoth Tape Drive
A Mammoth cartridge's tape measures 8mm across and a helical scan head is utilised to increase data transfer rate and capacity.
Each cartridge is capable of storing 40GB of compressed data. The compression algorithm used is known as Improved Data Recording Capability (IDRC) with a maximum compression ratio of 2:1.
The Mammoth drive can transfer data at speeds of up to 3MB/s without compression, and 6Mbps with compression. Mammoth2 is an improvement over Mammoth in terms of both capacity and transfer speed-up to 60GB (native) and 12MB/s without compression.
