1.
Magnetic tape data storage
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Magnetic tape data storage is a system for storing digital information on magnetic tape using digital recording. Modern magnetic tape is most commonly packaged in cartridges and cassettes, the device that performs writing or reading of data is a tape drive. Autoloaders and tape libraries automate cartridge handling, for example, a common cassette-based format is Linear Tape-Open, which comes in a variety of densities and is manufactured by several companies. Sony announced in 2014 that they had developed a storage technology with the highest reported magnetic tape data density,148 Gbit/in². Initially, magnetic tape for storage was wound on 10. 5-inch reels. This de facto standard for computer systems persisted through the late 1980s. Tape cartridges and cassettes were available as early as the mid-1970s and were used with small computer systems. With the introduction of the IBM3480 cartridge in 1984, large computer systems started to move away from open reel tapes, magnetic tape was first used to record computer data in 1951 on the Eckert-Mauchly UNIVAC I. The UNISERVO drive recording medium was a metal strip of 0. 5-inch wide nickel-plated phosphor bronze. Recording density was 128 characters per inch on eight tracks at a speed of 100 in/s. Of the eight tracks, six were data, one was a parity track, making allowance for the empty space between tape blocks, the actual transfer rate was around 7,200 characters per second. A small reel of mylar tape provided separation from the metal tape, IBM computers from the 1950s used ferrous-oxide coated tape similar to that used in audio recording. IBMs technology soon became the de facto industry standard, magnetic tape dimensions were 0. 5-inch wide and wound on removable reels up to 10.5 inches in diameter. Different tape lengths were available with 1,200 feet and 2,400 feet on mil, during the 1980s, longer tape lengths such as 3,600 feet became available using a much thinner PET film. Most tape drives could support a maximum size of 10.5 inches. CDC used IBM compatible 1/2 inch magnetic tapes, but also offered a 1 inch wide variant, a so-called mini-reel was common for smaller data sets, such as for software distribution. These were 7-inch reels, often with no fixed length—the tape was sized to fit the amount of data recorded on it as a cost-saving measure. Early IBM tape drives, such as the IBM727 and IBM729, were mechanically sophisticated floor-standing drives that used vacuum columns to buffer long u-shaped loops of tape
2.
Sony
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Sony Corporation is a Japanese multinational conglomerate corporation that is headquartered in Kōnan, Minato, Tokyo. Its diversified business includes consumer and professional electronics, gaming, entertainment, the company is one of the leading manufacturers of electronic products for the consumer and professional markets. Sony was ranked 116th on the 2015 list of Fortune Global 500 and these make Sony one of the most comprehensive entertainment companies in the world. The group consists of Sony Corporation, Sony Pictures Entertainment, Sony Interactive Entertainment, Sony Music Entertainment, Sony Financial Holdings and others. Sony is among the Semiconductor sales leaders by year and as of 2013, the companys current slogan is BE MOVED. Their former slogans were make. believe, like. no. other, Sony has a weak tie to the SMFG keiretsu, the successor to the Mitsui keiretsu. Sony began in the wake of World War II, in 1946, Masaru Ibuka started an electronics shop in a department store building in Tokyo. The company had $530 in capital and a total of eight employees, in the following year he was joined by his colleague, Akio Morita, and they founded a company called Tokyo Tsushin Kogyo 東京通信工業. The company built Japans first tape recorder, called the Type-G, in 1958 the company changed its name to Sony. When Tokyo Tsushin Kogyo was looking for a name to use to market themselves, they strongly considered using their initials. The primary reason they did not is that the railway company Tokyo Kyuko was known as TTK, the company occasionally used the acronym Totsuko in Japan, but during his visit to the United States, Morita discovered that Americans had trouble pronouncing that name. Another early name that was tried out for a while was Tokyo Teletech until Akio Morita discovered that there was an American company already using Teletech as a brand name, the name Sony was chosen for the brand as a mix of two words. One was the Latin word sonus, which is the root of sonic and sound, and the other was sonny, a common slang term used in 1950s America to call a boy. In the 1950s Japan sonny boys, was a word into Japanese which connoted smart and presentable young men. The first Sony-branded product, the TR-55 transistor radio, appeared in 1955, at the time of the change, it was extremely unusual for a Japanese company to use Roman letters to spell its name instead of writing it in kanji. The move was not without opposition, TTKs principal bank at the time and they pushed for a name such as Sony Electronic Industries, or Sony Teletech. Akio Morita was firm, however, as he did not want the company tied to any particular industry. Eventually, both Ibuka and Mitsui Banks chairman gave their approval, according to Schiffer, Sonys TR-63 radio cracked open the U. S. market and launched the new industry of consumer microelectronics
3.
Digital Linear Tape
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Digital Linear Tape is a magnetic tape data storage technology developed by Digital Equipment Corporation from 1984 onwards. In 1994, the technology was purchased by Quantum Corporation, who drives and licenses the technology. A variant with higher capacity is called Super DLT, the lower cost value line was initially manufactured by Benchmark Storage Innovations under license from Quantum. DEC launched the TK50 tape drive for the MicroVAX II and PDP-11 minicomputers in 1984 and this used 22-track CompacTape I cartridges, storing 94 MB per cartridge. The TK50 was superseded in 1987 by the TK70 drive and the 48-track CompacTape II cartridge, in 1989, the CompacTape III format was introduced, increasing the number of tracks to 128 and capacity to 2.6 GB. Later drives into the early 1990s improved the data density of the DLTtape III cartridge, the DLTtape IV cartridge was introduced by Quantum in 1994, with increased tape length and data density, initially offering 20 GB per tape. Super DLTtape, originally capable of up to 110 GB, was launched in 2001, DLT uses linear serpentine recording with multiple tracks on half-inch wide tape. The cartridges contain a reel and the tape is pulled out of the cartridge by means of a leader tape attached to the take-up reel inside the drive. The drive leader tape is buckled to the leader during the load process. Tape speed and tension are controlled electronically via the reel motors, the tape is guided by 4 to 6 rollers that touch only the back side of the tape. Tape material is metal particle tape, SDLT adds an optical servo system that reads servo patterns on the back of the tape to keep the data tracks on the front of the tape correctly aligned with the read/write heads. This is important for newer tape media, which have very thin, dLT7000 and 8000 tilt the head forward and backward to reduce crosstalk between adjacent tracks through azimuth, this is called Symmetric Phase Recording. All DLT drives support hardware data compression, all other companies/brands are contractors and/or resellers of these companies. A new naming convention took effect in 2005, calling the performance line DLT-S, DLT includes Write Once Read Many capability. In February 2007, Quantum stopped developing the next generations of DLT drives after insufficient market acceptance of the S4 and V4 drives, shifting its drive strategy to LTO. Once the media has been written to or formatted in a DLT4000 drive and this is because the DLT1/VS series use a different recording format that is not fully supported by the other family. Tapes written in value series drives can typically be read in higher end drives of a similar vintage, Symmetric Phase Recording DLTtape Handbook, Quantum,2001. How to rethread a dropped leader DLT Roadmap at dlttape. com Obituary of Dr. Fred Hertrich, ECMA209 Specification of DLT3
4.
Linear Tape-Open
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Hewlett Packard Enterprise, IBM and Quantum control the LTO Consortium, which directs development and manages licensing and certification of media and mechanism manufacturers. The standard form-factor of LTO technology goes by the name Ultrium, the seventh generation of LTO Ultrium was released in 2015 and can hold 6.0 TB in a cartridge of the same size. Upon introduction, LTO Ultrium rapidly defined the super tape market segment and has consistently been the best-selling super tape format, LTO is widely used with small and large computer systems, especially for backup. Half-inch magnetic tape has been used for storage for more than 60 years. In the mid 1980s, IBM and DEC put this kind of tape into a single reel, although the physical tape was nominally the same size, the technologies and intended markets were significantly different and there was no compatibility between them. IBM called its format 3480 and designed it to meet the requirements of its mainframe products. DEC originally called theirs CompacTape, but later it was renamed DLT, in the late 1980s, Exabytes Data8 format, derived from Sonys dual-reel cartridge 8 mm video format, saw some popularity, especially with UNIX systems. Sony followed this success with their own now-discontinued 8 mm data format, by the late 1990s, Quantums DLT and Sonys AIT were the leading options for high-capacity tape storage for PC servers and UNIX systems. These technologies were tightly controlled by their owners, consequently, there was little competition between vendors and the prices were relatively high. To counter this, IBM, HP and Seagate formed the LTO Consortium, much of the technology is an extension of the work done by IBM at its Tucson lab during the previous 20 years. Around the time of the release of LTO-1, Seagates magnetic tape division was spun off as Seagate Removable Storage Solutions, later renamed Certance, despite the initial plans for two form-factors of LTO technology, only Ultrium was ever produced. In common usage, LTO generally refers to the Ultrium form factor, as of 2015, seven generations of LTO Ultrium technology have been made available and three more are planned. Between generations, there are strict compatibility rules that describe how, notes Data capacity and speed figures above are for uncompressed data. Most manufacturers list compressed capacities on their marketing material, capacities are often stated on tapes as double the actual value, they assume that data will be compressed with a 2,1 ratio. See Compression below and the table above, the units for data capacity and data transfer rates generally follow the decimal SI prefix convention and not the binary prefix convention. Minimum and maximum reading and writing speeds are drive-dependent, in contrast to other tape technologies, an Ultrium cartridge is rigidly defined by a particular generation of LTO technology and cannot be used in any other way. While Ultrium drives are also defined by a generation, they are required to have some level of compatibility with older generations of cartridges. The rules for compatibility between generations of drives and cartridges is as follows, An Ultrium drive can read data from a cartridge in its own generation and the two prior generations
5.
Digital Data Storage
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Digital Data Storage is a computer data storage technology that is based upon the digital audio tape format that was developed during the 1980s. DDS is primarily intended for use as storage, especially for generating backup copies of working data. A DDS cartridge uses tape with a width of 3. 81mm, with the exception of the latest formats, DAT-160 and DAT-320, initially, the tape was 60 meters or 90 meters in length. Advancements in materials technology have allowed the length to be increased significantly in successive versions, a DDS tape drive uses helical scan recording, the same process used by a video cassette recorder. Backward compatibility between newer drives and older cartridges is not assured, for examples, see HPs DDS/DAT Media Compatibility Matrix, at one time, DDS competed against the Linear Tape-Open, Advanced Intelligent Tape, VXA, and Travan formats. However, AIT, Travan and VXA are no longer mainstream, stores up to 1.3 GB uncompressed on a 60 m cartridge or 2 GB uncompressed on a 90 m cartridge. A media recognition system was introduced with DDS-2 drives and cartridges to detect the medium type, from 1993, DDS-1 tapes included the media recognition system marks on the leader tape—a feature indicated by the presence of four vertical bars after the DDS logo. Stores up to 4 GB uncompressed on a 120 m cartridge, stores up to 12 GB uncompressed on a 125 m cartridge. DDS-3 uses PRML to minimize electronic noise for a data recording. DDS-4 stores up to 20 GB uncompressed on a 150 m cartridge and this format is also called DAT40. DAT72 stores up to 36 GB uncompressed on a 170 m cartridge, the DAT72 standard was developed by HP and Certance. It has the same form-factor as DDS-3 and -4 and is referred to as DDS-5. DAT160 was launched in June 2007 by HP, stores up to 80 GB uncompressed, a major change from the previous generations is the width of the tape. DAT160 uses 8 mm wide tape in a slightly thicker cartridge while all versions use 3.81 mm wide tape. Despite the difference in tape widths, DAT160 drives can load DAT-72, native capacity is 80 GB and native transfer rate was raised to 6.9 MB/s, mostly due to prolonging head/tape contact to 180°. Launch interfaces were Parallel SCSI and USB, with SAS interface released later, in November 2009 HP announced the DAT-320 standard, which stores up to 160 GB uncompressed per cartridge. The next format, Gen 8, was canceled, eCMA-139 ISO/IEC10777,1991, Specification of DDS. ECMA-146 ISO/IEC11321,1992, Specification of DATA/DAT, eCMA-150 ISO/IEC11557,1992, Specification of DDS-DC
6.
VXA
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VXA is a tape backup format originally created by Ecrix and now owned by Tandberg Data. After the merger between Ecrix and Exabyte, VXA was produced by Exabyte Corporation, on November 20,2006, Exabyte was purchased by Tandberg Data who has since stopped further development of the format. Exabyte and Ecrix describe the format as packet technology. Since VXA is based on helical scan technology, data is written across the tape from side to side in helical strips, the novel part of VXA packet technology is that each stripe starts with a unique packet ID and ends with an ECC packet checksum. As each stripe is written to tape, it is read back to verify that the write was successful. If the write was not 100% successful the packet can be rewritten at another point on the tape without stopping, when the data is read back, the packets are reassembled into a buffer by their packet ID. The buffer has 3 additional ECCs to ensure data integrity, another aspect of VXA is that there are 2 read heads for each stripe, slightly offset in relation to each other to allow for more flexibility in reading tapes written by other drives. Due to the relatively slow tape speed inherent to helical scan technology, the VXA format competes mainly against the DDS, and DLT-IV formats. Exabyte released two different product lines based on VXA-3 technology, VXA-320 in 2005 and VXA-172 in 2006, VXA-172 drives are limited to 86 GB per tape cartridge, but can be unlocked to remove the limit. VXA-3 was the first helical scan system in production to feature thin film MR heads, Data Capacity figures above are for uncompressed data. Exabyte assumes a 2x compression factor in their marketing material, ECMA222 Specification of ALDC, the data compression standard for VXA-1
7.
8 mm video format
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The 8mm video format refers informally to three related videocassette formats for the NTSC and PAL/SECAM television systems. These are the original Video8 format and its improved successor Hi8 and their user base consisted mainly of amateur camcorder users, although they also saw important use in the professional television production field. In 1985, Sony of Japan introduced the Handycam, one of the first Video8 cameras with commercial success, much smaller than the competitions VHS and Betamax video cameras, Video8 became very popular in the consumer camcorder market. The three formats are very similar, featuring both the same magnetic tape width and near-identical cassette shells, measuring 95 ×62.5 ×15 mm. This gives a measure of compatibility in some cases. One difference between them is in the quality of the tape itself, but the differences lie in the encoding of the video when it is recorded onto the tape. Video8 was the earliest of the three formats, and is entirely analog and it was followed by Hi8, a version with improved resolution. Although this was still analog, some professional Hi8 equipment could store additional digital stereo PCM sound on a reserved track. Digital8 is the most recent 8mm video format and it retains the same physical cassette shell as its predecessors, and can even record onto Video8 or Hi8 cassettes. However, the format in which video is encoded and stored on the tape itself is the entirely digital DV format, some Digital8 camcorders support Video8 and Hi8 with analog sound, but this is not required by the Digital8 specification. In all three cases, a length of 8mm-wide magnetic tape is wound between two spools and contained within a hard-shell cassette and these cassettes share similar size and appearance with the audio cassette, but their mechanical operation is far closer to that of VHS or Betamax videocassettes. Standard recording time is up to 180 minutes for PAL and 120 minutes for NTSC, like most other videocassette systems, Video8 uses a helical-scan 40mm head drum to read from and write to the magnetic tape. The drum rotates at high speed while the tape is pulled along the drums path, because the tape and drum are oriented at a slight angular offset, the recording tracks are laid down as parallel diagonal stripes on the tape. Unlike preceding systems, 8mm did not use a track on the tape to facilitate the head following the diagonal tracks. Instead 8mm recorded a sequence of four sine waves on each video track such that adjacent tracks would produce one of two heterodyne frequencies if the head mistracked, the system automatically adjusted the tracking such that the two frequencies produced were of equal magnitude. This system was derived from the track following used by the Philips Video 2000 system. Sony rechristened the system as automatic track following as the 8mm system lacked the ability of the heads to physically move within the head drum. The main disadvantage of the ATF system was that unlike in the case of a control track and this made editing using a non linear editing system problematic
8.
Helical scan
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Helical scan is a method of recording high frequency signals on magnetic tape. It is used in video tape recorders, video cassette recorders, digital audio tape recorders. In a fixed tape head recording system, magnetic tape is drawn past the head at a constant speed. The head creates a magnetic field in response to the signal to be recorded. As the tape moves away, the magnetic particles carry an imprint of the signal in their magnetic orientation. If the tape moves too slowly, a frequency signal will not be imprinted. Thus the bandwidth capacity of the recorded signal can be seen to be related to tape speed, the faster the speed. Digital video and digital audio need considerably more bandwidth than analog audio and this is impractical, since tapes of immense length would be required. The generally adopted solution is to rotate the head against the tape at high speed, so that the velocity is high. To accomplish this, the head must be tilted so that at each rotation of the head, each segment of the signal is recorded as a diagonal stripe across the tape. This is known as a helical scan because the tape wraps around the drum at an angle. The difference between the writing speed and linear tape speed is vast, for example,13 mph versus 35 mm/s. The helical scan method of recording was first developed by Eduard Schüller, with the advent of television broadcasting in Japan in the early 1950s, they saw the need for magnetic television signal recording just as engineers in the United States and Europe did. Thus, when tape motion was stopped, only a segment of the picture recording was present at the playback heads. The motivation to overcome this limitation led, in part, to the development of the helical scan system, toshiba introduced helical scan technology to the television industry in 1959. During the 1960s and 1970s, helical scan recording machines were introduced by many manufacturers and these factors also made it possible eventually to bring video recording to users at home, in a cassette format. There were a number of problems to be overcome with this system, the high tape/head speed could lead to rapid wear of both the tape and the head, so both need to be highly polished, and the head made of a hard, wear resistant material. Most systems operate with an air bearing separating the heads from the surface of the drum, supplying signals to a rotating head is also problematic, This is usually accomplished by coupling the signal inductively through a rotary transformer
9.
Hewlett-Packard
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The Hewlett-Packard Company or shortened to Hewlett-Packard was an American multinational information technology company headquartered in Palo Alto, California. The company was founded in a garage in Palo Alto by William Bill Redington Hewlett and David Dave Packard. HP was the worlds leading PC manufacturer from 2007 to Q22013 and it specialized in developing and manufacturing computing, data storage, and networking hardware, designing software and delivering services. HP also had services and consulting business around its products and partner products.4 billion in 2008, in November 2009, HP announced the acquisition of 3Com, with the deal closing on April 12,2010. On April 28,2010, HP announced the buyout of Palm, on September 2,2010, HP won its bidding war for 3PAR with a $33 a share offer, which Dell declined to match. On October 6,2014, Hewlett-Packard announced plans to split the PC and printers business from its enterprise products, the split closed on November 1,2015, and resulted in two publicly traded companies, HP Inc. and Hewlett Packard Enterprise. William Redington Hewlett and David Packard graduated with degrees in engineering from Stanford University in 1935. The company originated in a garage in nearby Palo Alto during a fellowship they had with a past professor, Terman was considered a mentor to them in forming Hewlett-Packard. In 1939, Packard and Hewlett established Hewlett-Packard in Packards garage with a capital investment of US$538. Hewlett and Packard tossed a coin to decide whether the company they founded would be called Hewlett-Packard or Packard-Hewlett, HP incorporated on August 18,1947, and went public on November 6,1957. Of the many projects they worked on, their very first financially successful product was an audio oscillator. This allowed them to sell the Model 200A for $54.40 when competitors were selling less stable oscillators for over $200, the Model 200 series of generators continued until at least 1972 as the 200AB, still tube-based but improved in design through the years. They worked on technology and artillery shell fuses during World War II. Hewlett-Packards HP Associates division, established around 1960, developed semiconductor devices primarily for internal use, instruments and calculators were some of the products using these devices. HP partnered in the 1960s with Sony and the Yokogawa Electric companies in Japan to develop several high-quality products, the products were not a huge success, as there were high costs in building HP-looking products in Japan. HP and Yokogawa formed a joint venture in 1963 to market HP products in Japan, HP bought Yokogawa Electrics share of Hewlett-Packard Japan in 1999. HP spun off a company, Dynac, to specialize in digital equipment. The name was picked so that the HP logo hp could be turned upside down to be a reverse image of the logo dy of the new company
