LTO stands for Linear-Tape Open.
Before explaining further, let us learn what is behind it.
LTO is a storage device, it stores data, reads data, and writes data on a magnetic tape.
Speaking about the magnetic tape, it is a tape made of a narrow strip of a plastic film having magnetized coating on them on one side. Now, to record, this reel of plastic is released from one reel and passes through a magnetic head which converts audio signals to magnetic fields and it also passes through the stabilizing rollers to guide the tape to roll on another reel. Any unexpected movement during this process will result in improper storage of data.
How did Linear Tape-Open come into existence?
Initially, magnetic tape was designed to record music. After German engineers introduced magnetophone during World War II, the same mechanism was adopted and developed by U.S. and British researchers and created a magnetic tape recorder in the 1940s and was widespread by the 1960s. It got introduced as a medium to store data in 1951s when it was used by UNIVAC I (Universal Automatic Computer) first commercial computer, in its auxiliary memory. It started to get popular and was preferred by large-scale researchers as it was able to store a big amount of data and replaced existing storage devices used by them.
It is known that magnetic tape is relatively cheaper than other modes of offline storage, data can be stored as archives. It is known for having a large memory capacity, so, it can be used for storing big files. Location of disk drive moves in seconds. It can store data from disks. Memory can be erased and new data can be stored, hence reusable. It is easy to stack the devices. Although with its benefits which are still required in this modern-day compared to the fact that it is an old concept, it comes with its drawbacks. It has a downside of being dirty easily since it has a magnetized coating, it is also required to let the machine work and watch it carefully while its processes as a single overlapping or a halt may destroy the whole strip or even sometimes the whole data. Now that you know that the whole process requires a tedious amount of effort, the same effort will be required after erasing data from it and again writing data in it.
Magnetic tapes are also used for commercial purposes but here it is focused on its use as storage. Magnetic tapes can be said to be of two types, one being reels moving in an enclosed cassette and another being the reels moving in a not an enclosed cassette. Due to the reels moving in an enclosed cassette the reels used to move slower compared to open reel cartridges. As a result, reel to reel systems was much preferred by people for their fidelity.
Now, Linear-Tape Open is a type of magnetic tape. Here the tape is referred to as open which means that it is an open format of storage. In the open format of storage, the format of file to store digital data is to be defined by a published specification and are normally maintained by an organization of standards and later can be used or implemented by anyone. In other words, the file format is free, proprietorial, and open-source software meaning it is accessible to people free and can be put into use for their own purpose.
Linear-Tape Open was developed in the 1990s, by Hewlett-Packard, International Business Machines, and Quantum who now control the LTO Consortium. LTO Consortium directs the development and manages to issue licenses and certificates to media and mechanism manufacturers.
In the 1980s, almost 30 years after reel to reel being introduced in the market, IBM and Digital Equipment Corporation decided to make reel to reel type of magnetic tape recording into a single reel and also in an enclosed cartridge. Although initially, the physical tape had the same size, targeted markets and technologies were very better. IBM called the format 3480, it was designed to meet the demand for requirements by the mainframe products. DEC called its format CompacTape but later got renamed to Digital Linear Tape and was sold to Quantum Corporation. Sony had a dual reel cartridge 8 mm video format, Advance Intelligent Tape, which had great fame but is now discontinued.
In the late 1990s, DLT and AIT became leading options to choose for high capacity tape storage for PC servers and Uniplexed Information and Computing System. After this HP, IBM and Seagate decided to form the LTO Consortium to introduce a more open format eyeing the mid-range segment of the market.
LTO tape can store for 15 to 30 years of archival storage. Although the durability of tape depends on the generation of the LTO, still I can be able to sustain 200-364 full file passes approximately.
Evolution of LTO Technology
Originally, LTO was defined as an optional data compression storage but with introduction of the generation of LTO, optional technology was introduced, which includes WORM, encryption, and partitioning features.
Streaming Lossless Data Compression, is the original LTO specification that describes a data compression method LTO-DC. In the data compression process, the original file is re-encoded to fewer bits to reduce the size of the files. In lossless data compression, the data is perfectly re-encoded whereas, in lossy compression, the data is approximately re-encoded.
Write once read many, WORM, was a capability in LTO-3. It is normally useful for legal record-keeping only. Later generations of LTO after LTO-3 will read but not erase or overwrite any data under a WORM cartridge. There is a unique WORM ID with every dataset and WORM capable drives able to quickly recognize WORM cartridges. WORM describes that the data storage cannot be modified once it’s written.
With growing generations, an encryption feature is added in LTO-4 so that the feature will allow the LTO-4 to encrypt the data before storing it. Although the LTO-4 is supposed to know every encryption process it is not supposed to run each one of them. Now every current LTO manufacturers support the original encryption in the tapes using Application Managed Encryption. An algorithm is used by LTO-4 and AES-GCM, which is more like an authorized key which is a symmetric block cipher. This key is what is used to encrypt and decrypt data and it can also mention if there are any changes in the data. Encryption can be said as a safety layer that prevents unauthorized access while converting data or information to a code.
In LTO-5 there were two partitions and in LTO-6 extended it to four partitions. Partitioning is a feature that allows its users to have flexibility. Partition feature is a process that portions out the library of the tape drives. Partition is a great feature since few partitions can be kept for certain use whereas the remaining partition can be open for use.
Linear Tape File System is used widely by computing systems due to it being an open standard and LTFS-formatted tapes. Due to the partition feature, the metadata are in a separate partition of tape. A standard description of an XML document which is readable by any LFTS-aware system is used by metadata which allows the data to be modified even though it is separate from the data is described.
Pros and Cons of LTO Technology
Pros: LTO gained its popularity mainly because it was proving huge storage and also the idea to have the reel to reel tape benefit in a single reel and also in a closed compact cartridge was definite to reap benefits. Since the drive is in the industry for decades it is widely used and accepted as an industry standard. Typical but the drivers are complex at the core which provides security and liability. It is known to have a low cost for producing storage media. Linear Tape File System helps in accessing the files from disks similar to LTO. Most importantly it provides disaster recovery options for high-value content.
Cons: Although it has its benefits to its users, it also has the not-so benefit part that comes with it. LTO is required to be updated regularly and hence time-consuming. As mention them to be magnetic, they do attract dirt which is why it is required to keep them clean. It is not quick to update changes. Tape drives need to be labeled, sorted, and properly organized.
The magnetic tape was already here with us for more than 60 years and LTO can be said to be seen as a huge success. LTO is in the market for around 20-30 years now and with increasing time LTO generations did come up with huge hits of tape drives in the market. Demand for storage to store data about people is increasing daily. There are millions of data that is required to be stored let it about people, history, researches, inventions, recordings of speeches and music, definitely storage space is required. Now with all these data stored in the tape drives, the data are in physical form and this physical form of data is now required to be stored in such a way that that it is easy to find and easy to maintain. Lastly, with upcoming generations and great features, we can hope it will overcome its drawbacks as well.