What Is A Bank vault Wiki

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A bank vault is a secure space where money, valuables, records, and documents are stored. It is intended to protect their contents from theft, unauthorized use, fire, natural disasters, and other threats, much like a safe. Unlike safes, vaults are an integral part of the building within which they are built, using armored walls and a tightly fashioned door closed with a complex lock.

Historically, strongrooms were built in the basements of banks where the ceilings were vaulted, hence the name. Modern bank vaults typically contain many safe deposit boxes, as well as places for teller cash drawers and other valuable assets of the bank or its customers. They are also common in other buildings where valuables are kept such as post offices, grand hotels, rare book libraries and certain government ministries.

Vault technology developed in a type of arms race with bank robbers. As burglars came up with new ways to break into vaults, vault makers found new ways to foil them. Modern vaults may be armed with a wide array of alarms and anti-theft devices. Some 19th and early 20th century vaults were built so well that today they are difficult to destroy, even with specialized demolition equipment. These older vaults were typically made with steel-reinforced concrete. The walls were usually at least 1 ft (0.3 m) thick, and the door itself was typically 3.5 ft (1.1 m) thick. Total weight ran into the hundreds of tons (see the Federal Reserve Bank of Cleveland). Today vaults are made with thinner, lighter materials that, while still secure, are easier to dismantle than their earlier counterparts.

The need for secure storage stretches far back in time. The earliest known locks were made by the Egyptians. Ancient Romans used a more sophisticated locking system, called warded locks. Warded locks had special notches and grooves that made picking them more difficult. Lock technology advanced independently in ancient India, Russia, and China, where the combination lock is thought to have originated. In the United States, most banks relied on small iron safes fitted with a key lock up until the middle of the nineteenth century. After the Gold Rush of 1849, unsuccessful prospectors turned to robbing banks. The prospectors would often break into the bank using a pickaxe and hammer. The safe was usually small enough that the thief could get it out a window, and take it to a secluded spot to break it open.

Banks demanded more protection and safe makers responded by designing larger, heavier safes. Safes with a key lock were still vulnerable through the key hole, and bank robbers soon learned to blast off the door by pouring explosives in this opening. In 1861, inventor Linus Yale Jr. introduced the modern combination lock. Bankers quickly adopted Yale's lock for their safes, but bank robbers came up with several ways to get past the new invention. It was possible to use force to punch the combination lock through the door. Other experienced burglars learned to drill holes into the lock case and use mirrors to view the slots in the combination wheels inside the mechanism. A more direct approach was to simply kidnap the bank manager and force him to reveal the combination.

After the inventions of the combination lock, James Sargent—an employee of Yale—developed the "theft-proof lock". This was a combination lock that worked on a timer. The vault or safe door could only be opened after a set number of hours had passed, thus a kidnapped bank employee could not open the lock in the middle of the night even under force. Time locks became widespread at banks in the 1870s. This reduced the kidnappings, but set bank robbers to work again at prying or blasting open vaults. Thieves developed tools for forcing open a tiny crack between the vault door and frame. As the crack widened, the thieves levered the door open or poured in gunpowder and blasted it off. Vault makers responded with a series of stair-stepped grooves in the door frame so the door could not be levered open. But these grooves proved ideal for a new weapon: liquid nitroglycerin. Professional bank robbers learned to boil dynamite in a kettle of water and skim the nitroglycerin off the top. They could drip this volatile liquid into the door grooves and destroy the door. Vault makers subsequently redesigned their doors so they closed with a thick, smooth, tapered plug. The plug fit so tightly that there was no room for the nitroglycerin.

Vault lock and two keys from the National German American Bank in Saint Paul, Minnesota, 1856

By the 1920s, most banks avoided using safes and instead turned to gigantic, heavy vaults with walls and doors several feet thick. These were meant to withstand not only robbers but also angry mobs and natural disasters. Despite the new security measures, these vaults were still vulnerable to yet another new invention, the cutting torch. Burning oxygen and acetylene gas at about 6,000 °F (3,300 °C), the torch could easily cut through steel. It was in use as early as 1907, but became widespread with World War I. Robbers used cutting torches in over 200 bank robberies in 1924 alone. Manufacturers learned to sandwich a copper alloy into vault doors. If heated, the high thermal conductivity of copper dissipates the heat to prevent melting or burning. After this design improvement, bank burglaries fell off and were far less common at the end of the 1920s than at the beginning of the decade.

Technology continues in the race with bank robbers, coming up with new devices such as heat sensors, motion detectors, and alarms. Bank robbers have in turn developed even more technological tools to find ways around these systems. Although the number of bank robberies has been cut dramatically, they are still attempted.

Materials used in vaults and vault doors have changed as well. The earlier vaults had steel doors, but because these could easily be cut by torches, different materials were tried. Massive cast iron doors had more resistance to acetylene torches than steel. The modern preferred vault door material is the same concrete as used in the vault wall panels. It is usually clad in steel for cosmetic

Design
Vault of a retail bank under demolition

Bank vaults are built as custom orders. The vault is usually the first aspect of a new bank building to be designed and built. The manufacturing process begins with the design of the vault, and the rest of the bank is built around it. The vault manufacturer consults with the customer to determine factors such as the total vault size, desired shape, and location of the door. After the customer signs off on the design, the manufacturer configures the equipment to make the vault panels and door. The customer usually orders the vault to be delivered and installed. That is, the vault manufacturer not only makes the vault parts, but brings the parts to the construction site and puts them together.

Bank vaults are typically made with steel-reinforced concrete. This material was not substantially different from that used in construction work. It relied on its immense thickness for strength. An ordinary vault from the middle of the 20th century might have been 18 in (45.72 cm) thick and was quite heavy and difficult to remove or remodel around. Modern bank vaults are now typically made of modular concrete panels using a special proprietary blend of concrete and additives for extreme strength. The concrete has been engineered for maximum crush resistance. A panel of this material, though only 3 in (7.62 cm) thick, may be up to 10 times as strong as an 18 in-thick (45.72-cm) panel of regular formula concreted. There are at least two public examples of vaults withstanding a nuclear blast. The most famous is the Teikoku Bank in Hiroshima whose two Mosler Safe Company vaults survived the atomic blast with all contents intact. The bank manager wrote a congratulatory note to Mosler. A second is a vault at the Nevada National Security Site (formerly the Nevada Test Site) in which an above ground Mosler vault was one of many structures specifically constructed to be exposed to an atomic blast

Panels
Fichet Paris, Vault of Crédit Lyonnais

The wall panels are molded first using a special reinforced concrete mix. In addition to the usual cement powder, stone, etc., additional materials such as metal shavings or abrasive materials may be added to resist drilling penetration of the slab. Unlike regular concrete used in construction, the concrete for bank vaults is so thick that it cannot be poured. The consistency of concrete is measured by its "slump". Vault concrete has zero slump. It also sets very quickly, curing in only six to 12 hours, instead of the three to four days needed for most concrete.


 * A network of reinforcing steel rods are manually placed into the damp mix.
 * The molds are vibrated for several hours. The vibration settles the material and eliminates air pockets.
 * The edges are smoothed with a trowel, and the concrete is allowed to harden.
 * The panels are removed from the mold and placed on a truck for transport to the customer's construction site.

Door
The vault door is also molded of special concrete used to make the panels, but it can be made in several ways. The door mold differs from the panel molds because there is a hole for the lock and the door will be clad in stainless steel. Some manufacturers use the steel cladding as the mold and pour the concrete directly into it. Other manufacturers use a regular mold and screw the steel on after the panel is dry.

Round vault doors were popular in the early 20th century and are iconic images for a bank's high security. They fell out of favor due to manufacturing complexities, maintenance issues (door sag due to weight) and cost, but a few examples are still available.

A day gate is a second door inside the main vault door frame used for limited vault protection while the main door is open. It is often made of open metal mesh or glass and is intended to keep a casual visitor out rather than to provide true security.

Lock
A vault door, much like the smaller burglary safe door, is secured with numerous massive metal bolts (cylinders) extending from the door into the surrounding frame. Holding those bolts in place is some sort of lock. The lock is invariably mounted on the inside (behind) of the difficult-to-penetrate door and is usually very modest in size and strength, but very difficult to gain access to from the outside. There are many types of lock mechanisms in use:


 * A combination lock similar in principle to that of a padlock or safe door is very common. This is usually a mechanical device but products incorporating both mechanical and electronic mechanisms are available, making certain safe cracking techniques very difficult.
 * Some high-end vaults employ a two piece key to be used in conjunction with a combination lock. This key consists of a long stem as well as a short stamp which should be safe guarded separately and joined together to open the vault door.
 * A dual control (dual custody) combination lock has two dials controlling two locking mechanisms for the door. They are usually configured so that both locks must be dialed open at the same time for the door to be unlocked.  No single person is given both combinations, requiring two people to cooperate to open the door. Some doors may be configured so that either dial will unlock the door, trading off increased convenience for lessened security.
 * A time lock is a clock that prevents the vault's door from opening until a specified number of hours have passed. This is still the "theft proof" lock system that Sargent invented in the late nineteenth century. Such locks are manufactured by only a few companies worldwide. The locking system is supplied to the vault manufacturer preassembled.
 * Many safe-cracking techniques also apply to the locking mechanism of the vault door. They may be complicated by the sheer thickness and strength of the door and panel.

Installation

 * The finished vault panels, door, and lock assembly are transported to the bank construction site. The vault manufacturer's workers then place the panels enclosed in steel at the designated spots and weld them together. The vault manufacturer may also supply an alarm system, which is installed at the same time. While older vaults employed various weapons against burglars, such as blasts of steam or tear gas, modern vaults instead use technological countermeasures. They can be wired with a listening device that picks up unusual sounds, or observed with a camera. An alarm is often present to alert local police if the door or lock is tampered with.

US resistance standards
Quality control for much of the world's vault industry is overseen by Underwriters Laboratories, Inc. (UL), in Northbrook, Illinois. Until 1991, the United States government also regulated the vault industry. The government set minimum standards for the thickness of vault walls, but advances in concrete technology made thickness an arbitrary measure of strength. Thin panels of new materials were far stronger than the thicker, poured concrete walls. Now the effectiveness of the vault is measured by how well it performs against a mock break-in. Manufacturers also do their own testing designing a new product to make sure it is likely to succeed in UL trials. Key points include:


 * It is based on using "common hand tools, picking tools, mechanical or portable electric tools, grinding points carbide drills, pressure applying devices or mechanisms, abrasive cutting wheels, power saws, coring tools, impact tools, fluxing rods, and oxy-fuel gas cutting torches".
 * A breach is a hole in the door or wall of at least 96 square inches (6 × 16 in (15.24 × 40.64 cm)) or breaking locking bolts to allow the door to open.
 * Considers only the time actually spent working (excludes setup, rests, etc.)
 * Does not cover attacks with a thermal lance or explosives.
 * UL-608 makes no claims as to the fire resistance of the vault.
 * Applies to the door and all sides.
 * The lock, ventilation, alarms, etc. are covered by other UL standards.

European resistance standards
As with the US, Europe has agreed a series of test standards to assure a common view of penetrative resistance to forcible attack. The testing regime is covered under the auspices of Euronorm 1143-1:2012 (also known as BS EN 1143-1: 2012), which can be purchased from approved European standards agencies.

Key points include:

A modern highly portable core drill

An explosive door breaching test


 * Standard covers burglary resistance tests against free-standing safes and ATMs, as well as strongrooms and doors
 * Tests are undertaken to arrive at a grade (0 to XIII) with two extra resistance qualifiers (one for the use of explosives the other for core drills)
 * Test attack tools fall into five categories with increasing penetrative capability, i.e. Categories A–D and S
 * Penetration success is measured as partial (125mm diameter hole) or full (350mm diameter hole)
 * Considers only the time actually spent working (excludes setup, rests, etc.)
 * EN 1143-1 makes no claims as to the fire resistance of the vault
 * EN 1300 covers high security locks, i.e. four lock classes (A, B, C and D)
 * Applies to the door and all vault sides.

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Magnetic-tape data storage
Magnetic-tape data storage is a system for storing digital information on magnetic tape using digital recording.

Tape was an important medium for primary data storage in early computers, typically using large open reels of 7-track, later 9-track tape. Modern magnetic tape is most commonly packaged in cartridges and cassettes, such as the widely supported Linear Tape-Open (LTO) and IBM 3592 series. The device that performs the writing or reading of data is called a tape drive. Autoloaders and tape libraries are often used to automate cartridge handling and exchange. Compatibility was important to enable transferring data.

Tape data storage is now used more for system backup, data archive and data exchange. The low cost of tape has kept it viable for long-term storage and archive.

Open reels
Initially, magnetic tape for data storage was wound on 10.5-inch (27 cm) reels. This standard for large computer systems persisted through the late 1980s, with steadily increasing capacity due to thinner substrates and changes in encoding. Tape cartridges and cassettes were available starting in the mid-1970s and were frequently used with small computer systems. With the introduction of the IBM 3480 cartridge in 1984, described as "about one-fourth the size ... yet it stored up to 20 percent more data", large computer systems started to move away from open-reel tapes and towards cartridges.

UNIVAC
Magnetic tape was first used to record computer data in 1951 on the UNIVAC I. The UNISERVO drive recording medium was a thin metal strip of 0.5-inch (12.7 mm) wide nickel-plated phosphor bronze. Recording density was 128 characters per inch (198 micrometres per character) on eight tracks at a linear speed of 100 in/s (2.54 m/s), yielding a data rate of 12,800 characters per second. Of the eight tracks, six were data, one was for parity, and one was a clock, or timing track. Making allowances 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 and the read/write head.

IBM formats
10+1⁄2-inch (270 mm) diameter reel of 9-track tape

IBM computers from the 1950s used ferric-oxide-coated tape similar to that used in audio recording. IBM's technology soon became the de facto industry standard. Magnetic tape dimensions were 0.5-inch (12.7 mm) wide and wound on removable reels. Different tape lengths were available with 1,200 feet (370 m) and 2,400 feet (730 m) on mil and one half thickness being somewhat standard.[clarification needed] During the 1980s, longer tape lengths such as 3,600 feet (1,100 m) became available using a much thinner PET film. Most tape drives could support a maximum reel size of 10.5 inches (267 mm). A so-called mini-reel was common for smaller data sets, such as for software distribution. These were 7-inch (18 cm) reels, often with no fixed length—the tape was sized to fit the amount of data recorded on it as a cost-saving measure.[citation needed]

CDC used IBM-compatible 1⁄2-inch (13 mm) magnetic tapes, but also offered a 1-inch-wide (25 mm) variant, with 14 tracks (12 data tracks corresponding to the 12-bit word of CDC 6000 series peripheral processors, plus 2 parity bits) in the CDC 626 drive.

Early IBM tape drives, such as the IBM 727 and IBM 729, were mechanically sophisticated floor-standing drives that used vacuum columns to buffer long u-shaped loops of tape. Between servo control of powerful reel motors, a low-mass capstan drive, and the low-friction and controlled tension of the vacuum columns, fast start and stop of the tape at the tape-to-head interface could be achieved. The fast acceleration is possible because the tape mass in the vacuum columns is small; the length of tape buffered in the columns provides time to accelerate the high-inertia reels. When active, the two tape reels thus fed tape into or pulled tape out of the vacuum columns, intermittently spinning in rapid, unsynchronized bursts, resulting in visually striking action. Stock shots of such vacuum-column tape drives in motion were ironically used to represent computers in movies and television.

Early half-inch tape had 7 parallel tracks of data along the length of the tape, allowing 6-bit characters plus 1 bit of parity written across the tape. This was known as 7-track tape. With the introduction of the IBM System/360 mainframe, 9-track tapes were introduced to support the new 8-bit characters that it used. The end of a file was designated by a special recorded pattern called a tape mark, and end of the recorded data on a tape by two successive tape marks. The physical beginning and end of usable tape was indicated by reflective adhesive strips of aluminum foil placed on the backside.[citation needed]

Recording density increased over time. Common 7-track densities started at 200 characters per inch (CPI), then 556, and finally 800; 9-track tapes had densities of 800 (using NRZI), then 1600 (using PE), and finally 6250 (using GCR). This translates into about 5 megabytes to 140 megabytes per standard length (2,400 ft, 730 m) reel of tape. Effective density also increased as the interblock gap (inter-record gap) decreased from a nominal 3⁄4 inch (19 mm) on 7-track tape reel to a nominal 0.30 inches (7.6 mm) on a 6250 bpi[clarification needed] 9-track tape reel.

At least partly due to the success of the System/360, and the resultant standardization on 8-bit character codes and byte addressing, 9-track tapes were very widely used throughout the computer industry during the 1970s and 1980s. IBM discontinued new reel-to-reel products replacing them with cartridge based products beginning with its 1984 introduction of the cartridge-based 3480 family.

DEC format
LINCtape, and its derivative, DECtape were variations on this "round tape". They were essentially a personal storage medium, used tape that was 0.75 inches (19 mm) wide and featured a fixed formatting track which, unlike standard tape, made it feasible to read and rewrite blocks repeatedly in place. LINCtapes and DECtapes had similar capacity and data transfer rate to the diskettes that displaced them, but their access times were on the order of thirty seconds to a minute.

Cartridges and cassettes
Quarter-inch cartridges

In the context of magnetic tape, the term cassette or cartridge means a length of magnetic tape in a plastic enclosure with one or two reels for controlling the motion of the tape. The type of packaging affects the load and unload times as well as the length of tape that can be held. In a single-reel cartridge, there is a takeup reel in the drive while a dual reel cartridge has both takeup and supply reels in the cartridge. A tape drive uses one or more precisely controlled motors to wind the tape from one reel to the other, passing a read/write head as it does.

An IBM 3590 data cartridge can hold up to 10GiB uncompressed.

A different type is the endless tape cartridge, which has a continuous loop of tape wound on a special reel that allows tape to be withdrawn from the center of the reel and then wrapped up around the edge, and therefore does not need to rewind to repeat. This type is similar to a single-reel cartridge in that there is no take-up reel inside the tape drive.

The IBM 7340 Hypertape drive, introduced in 1961, used a dual reel cassette with a 1-inch-wide (2.5 cm) tape capable of holding 2 million six-bit characters per cassette.

In the 1970s and 1980s, audio Compact Cassettes were frequently used as an inexpensive data storage system for home computers, or in some cases for diagnostics or boot code for larger systems such as the Burroughs B1700. Compact cassettes are logically, as well as physically, sequential; they must be rewound and read from the start to load data. Early cartridges were available before personal computers had affordable disk drives, and could be used as random access devices, automatically winding and positioning the tape, albeit with access times of many seconds.

In 1984 IBM introduced the 3480 family of single reel cartridges and tape drives which were then manufactured by a number of vendors through at least 2004. Initially providing 200 megabytes per cartridge, the family capacity increased over time to 2.4 gigabytes per cartridge. DLT (Digital Linear Tape), also a cartridge-based tape, was available beginning 1984 but as of 2007 future development was stopped in favor of LTO.

In 2003 IBM introduced the 3592 family to supersede the IBM 3590. While the name is similar, there is no compatibility between the 3590 and the 3592. Like the 3590 and 3480 before it, this tape format has 1⁄2-inch (13 mm) tape spooled into a single reel cartridge. Initially introduced to support 300 gigabytes, the sixth generation released in 2018 supports a native capacity of 20 terabytes.

Linear Tape-Open (LTO) single-reel cartridge was announced in 1997 at 100 megabytes and in its eighth generation supports 12 terabytes in the same sized cartridge. As of 2019 LTO has completely displaced all other tape technologies in computer applications, with the exception of some IBM 3592 family at the high-end.

Linear density
Bytes per inch (BPI) is the metric for the density at which data is stored on magnetic media. The term BPI can refer to bits per inch, but more often refers to bytes per inch.

The term BPI can mean bytes per inch when the tracks of a particular format are byte-organized, as in 9-track tapes.

Tape width
The width of the media is the primary classification criterion for tape technologies. One-half-inch (13 mm) has historically been the most common width of tape for high-capacity data storage. Many other sizes exist and most were developed to either have smaller packaging or higher capacity.[citation needed]

Recording method
Linear Recording method is also an important way to classify tape technologies, generally falling into two categories: linear and scanning.

Linear
Linear serpentine

The linear method arranges data in long parallel tracks that span the length of the tape. Multiple tape heads simultaneously write parallel tape tracks on a single medium. This method was used in early tape drives. It is the simplest recording method, but also has the lowest data density.

A variation on linear technology is linear serpentine recording, which uses more tracks than tape heads. Each head still writes one track at a time. After making a pass over the whole length of the tape, all heads shift slightly and make another pass in the reverse direction, writing another set of tracks. This procedure is repeated until all tracks have been read or written. By using the linear serpentine method, the tape medium can have many more tracks than read/write heads. Compared to simple linear recording, using the same tape length and the same number of heads, data storage capacity is substantially higher.

Scanning
Helical

Scanning recording methods write short dense tracks across the width of the tape medium, not along the length. Tape heads are placed on a drum or disk which rapidly rotates while the relatively slow-moving tape passes it.

An early method used to get a higher data rate than the prevailing linear method was transverse scan. In this method, a spinning disk with the tape heads embedded in the outer edge is placed perpendicular to the path of the tape. This method is used in Ampex's DCRsi instrumentation data recorders and the old Ampex quadruplex videotape system. Another early method was arcuate scan. In this method, the heads are on the face of a spinning disk which is laid flat against the tape. The path of the tape heads forms an arc.

Helical scan recording writes short dense tracks in a diagonal manner. This method is used by virtually all current videotape systems and several data tape formats.

Block layout and speed matching
In a typical format, data is written to tape in blocks with inter-block gaps between them, and each block is written in a single operation with the tape running continuously during the write. However, since the rate at which data is written or read to the tape drive varies as a tape drive usually has to cope with a difference between the rate at which data goes on and off the tape and the rate at which data is supplied or demanded by its host.

Various methods have been used alone and in combination to cope with this difference. If the host cannot keep up with the tape drive transfer rate, the tape drive can be stopped, backed up, and restarted (known as shoe-shining). A large memory buffer can be used to queue the data. In the past, the host block size affected the data density on tape, but on modern drives, data is typically organized into fixed-sized blocks which may or may not be compressed or encrypted, and host block size no longer affects data density on tape. Modern tape drives offer a speed matching feature, where the drive can dynamically decrease the physical tape speed as needed to avoid shoe-shining.

In the past, the size of the inter-block gap was constant, while the size of the data block was based on host block size, affecting tape capacity – for example, on count key data storage. On most modern drives, this is no longer the case. Linear Tape-Open type drives use a fixed-size block for tape (a fixed-block architecture), independent of the host block size, and the inter-block gap is variable to assist with speed matching during writes.

On drives with compression, the compressibility of the data will affect the capacity.[how?]

Sequential access to data
Tape is characterized by sequential access to data. While tape can provide fast data transfer, it takes tens of seconds to load a cassette and position the tape head to selected data. By contrast, hard disk technology can perform the equivalent action in tens of milliseconds (3 orders of magnitude faster) and can be thought of as offering random access to data.

File systems require data and metadata to be stored on the data storage medium. Storing metadata in one place and data in another, as is done with disk-based file systems, requires repositioning activity. As a result, most tape systems use a simplified filesystem in which files are addressed by number, not by filename. Metadata such as file name or modification time is typically not stored at all. Tape labels store such metadata, and they are used for interchanging data between systems. File archiver and backup tools have been created to pack multiple files along with the related metadata into a single tape file. Serpentine tape drives (e.g., QIC) offer improved access time by switching to the appropriate track; tape partitions are used for directory information. The Linear Tape File System is a method of storing file metadata on a separate part of the tape. This makes it possible to copy and paste files or directories to a tape as if it were a disk, but does not change the fundamental sequential access nature of tape.

Access time
Tape has a long random access time since the deck must wind an average of one-third the tape length to move from one arbitrary position to another. Tape systems attempt to alleviate the intrinsic long latency, either using indexing, where a separate lookup table (tape directory) is maintained which gives the physical tape location for a given data block number (a must for serpentine drives), or by marking blocks with a tape mark that can be detected while winding the tape at high speed

Data compression
Most tape drives now include some kind of lossless data compression. There are several algorithms that provide similar results: LZW (widely supported), IDRC (Exabyte), ALDC (IBM, QIC) and DLZ1 (DLT). Embedded in tape drive hardware, these compress a relatively small buffer of data at a time, so cannot achieve extremely high compression even of highly redundant data. A ratio of 2:1 is typical, with some vendors claiming 2.6:1 or 3:1. The ratio actually obtained depends on the nature of the data so the compression ratio cannot be relied upon when specifying the capacity of equipment, e.g., a drive claiming a compressed capacity of 500 GB may not be adequate to back up 500 GB of real data. Data that is already stored efficiently may not allow any significant compression and a sparse database may offer much larger factors. Software compression can achieve much better results with sparse data, but uses the host computer's processor, and can slow the backup if the host computer is unable to compress as fast as the data is written.

The compression algorithms used in low-end products are not the most effective known today, and better results can usually be obtained by turning off hardware compression AND using software compression (and encryption if desired) instead.

Plain text, raw images, and database files (TXT, ASCII, BMP, DBF, etc.) typically compress much better than other types of data stored on computer systems. By contrast, encrypted data and pre-compressed data (PGP, ZIP, JPEG, MPEG, MP3, etc.) normally increase in size if data compression is applied. In some cases, this data expansion could be as much as 15%.

Encryption
Standards exist to encrypt tapes. Encryption is used so that even if a tape is stolen, the thieves cannot use the data on the tape. Key management is crucial to maintain security. Compression is more efficient if done before encryption, as encrypted data cannot be compressed effectively due to the entropy it introduces. Some enterprise tape drives can quickly encrypt data. Symmetric streaming encryption algorithms[which?] can also provide high performance[citation needed].

Cartridge memory and self-identification
Some tape cartridges, notably LTO cartridges, have small associated data storage chips built into the cartridges to record metadata about the tape, such as the type of encoding, the size of the storage, dates and other information. It is also common[citation needed] for tape cartridges to have bar codes on their labels in order to assist an automated tape library.

Viability
Tape remains viable in modern data centers because:


 * 1) it is the lowest cost medium for storing large amounts of data;
 * 2) as a removable medium it allows the creation of an air gap which can prevent data from being hacked, encrypted or deleted;
 * 3) its longevity allows for extended data retention which may be required by regulatory agencies.

The lowest cost tiers of cloud storage can also be tape.

High-density magnetic media
In 2014, Sony announced that they had developed, using a new vacuum thin-film forming technology able to form extremely fine crystal particles, a tape storage technology with the highest reported magnetic tape data density, 148 Gbit/in² (23 Gbit/cm²), potentially allowing a native tape capacity of 185 TB. It was further developed by Sony, with announcement in 2017, about reported data density of 201 Gbit/in² (31 Gbit/cm²), giving standard compressed tape capacity of 330 TB.

In May 2014, Fujifilm followed Sony and made an announcement that it will develop a 154 TB tape cartridge in conjunction with IBM, which will have an areal data storage density of 85.9 GBit/in² (13.3 billion bits per cm²) on linear magnetic particulate tape. The technology developed by Fujifilm, called NANOCUBIC, reduces the particulate volume of BaFe magnetic tape, simultaneously increasing the smoothness of the tape, increasing the signal to noise ratio during read and write while enabling high-frequency response.

In December 2020, Fujifilm and IBM announced technology that could lead to a tape cassette with a capacity of 580 terabytes, using strontium ferrite as the recording medium.

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