Tape drives have their own unique history of technical excellence. For the first time, this type of data storage appeared in the middle of the 20th century and established itself as an immutable device for recording, reading and storing data.
Description and principle of operation
A tape drive or tape drive is a storage device that operates on the principle of magnetic data recording on a tape format medium. After recording data, you can use them for various purposes, and the principle of operation is no different from a household tape recorder.
Today, in some areas, tape drives are still widely used. The main purpose is to write and read data, as well as copy and archive it. Recording occurs by storing information, fixing it on the drive in parallel across all tracks. When operating a magnetic tape drive, the tape itself can make movements in both directions. In fact, the workflow resembles the use of a tape recorder, since at the end of the recording, when the tape ends, the unit moves it in the opposite direction.
The amount of storage information depends only on the footage of the magnetic tape itself. It is the length of the tape that determines the size of the data record.
Appearance story
In the mid-20th century, Eckert-Mauchly Computer Corporation recorded for the first time on a tape drive for computer data, and the UNIVAC I computer participated in this.
The storage medium was Vicalloy, which was made of a thin strip of metal 12.65 mm wide, consisting of nickel-plated bronze.
Before hard drives appeared, tape drives were firmly embedded in computers, acting as the main and long-term storage medium. Later, such storages began to be used only in cases where data was rarely used. Then, tape drives became portable storage for a huge amount of data.
The very first machine, which appeared in 1951, was called UNISERVO and could store a data volume of 224 kilobytes. This drive used nickel-phosphorus bronze as materials for the tape.
The following year, IBM released a model with seven tracks on a tape, the composition of which became plastic. Such a tape stored six bit bytes and one parity bit.
In 1958, a more advanced model appeared with separate heads for writing and reading. The improvement was that the computer could read data after they were written. There is information that a museum in California just stores information on such a drive.
A nine-track tape appeared in 1964. The principle of operation is the same as that of the 1952 model - 8 bit bytes and a parity bit.
For ten years, from 1970 to 1980, many models appeared with the following innovations:
- Automatic reel loading.
- The ability to recover data and correct it.
- Using drives as a library.
- Audio tapes were put into operation.
- Using a RAM buffer in order to minimize the delay between start / stop operations.
- The amount of stored information grows to 20 megabytes.
For 2014, there is already a model that supports working with LTFS technology, operating according to the file scheme. That is, the device directly opens access to the necessary information, avoiding the full scroll of the tape. The amount of data increased to 10 terabytes. Today, there are drives with a large amount of memory that are used on an industrial scale.
Tape on nine tracks
Since industrial computers could occupy an entire room of medium size in the last century, the use of NML (magnetic tape drive) was widespread.
Such a tape drive was most popular in the USSR in the 70-80s of the last century.
Using Audio Cassettes
The cassette for the tape recorder has the same principle of operation. It can also be called a tape drive. Having a primitive tape recorder in the house, anyone could record songs and listen to music.
Until the mid-90s, some types of computers could work with drives such as audio cassettes.
Modern representatives
Current streamers have the ability to connect using the high-performance SAS interface, which is capable of providing data rates from three to six gigabits per second. Older representatives of IBM models connected via the FICON connector.
Description of LTO Technology
Today's representatives of magnetic drives adhere to standards called LTO. IBM introduced the LTO-5 TS2350 tape drive (tape drive), which has two SAS connectors and one port for Internet access.
Applicable Operating Systems
Working with multi-tasking and multi-user operating systems seems to be the simplest way, that is, commands such as tar and mt are used. However, with the Mac operating system, the first command is not able to work with streamers, and the second command is simply missing. The main operating system for working with magnetic tapes is Linux and Mac OS X.
For a wide range of operating systems, there are special programs for servicing modern streamers. Since 2010, IBM has been working on the implementation of tape drives in Windows.
Tape Library Description
The principle of operation of such a library is that it operates simultaneously with several tape drives. Libraries of this magnitude are completely robotic. Such storages work with barcode-labeled cassettes, which the robot takes out according to a given program.
Compared to disk media, this type of data storage is much more profitable, since maintaining a tape library requires less energy consumption and the total cost of equipment is much less than disk analogues.
Pros and cons
Among the advantages, as mentioned above, there is a low cost and maintenance of this type of storage. A positive point is the possibility of endless data recording, that is, the amount of memory is almost unlimited. Due to the monotonous operations and the mechanical structure, tape drives are able to last quite a long time, namely, decades.
Unfortunately, there are also disadvantages of using the tape library - this is a slow data access speed. The fact is that in order to read certain information, the tape needs time to scroll to a given place. The same thing happens if you activate multiple requests at the same time.
Despite the low consumption of resources, the cost of the tape drive itself is very high, so the price of a recording device is one of the drawbacks.