MariaDB is a community-developed, commercially supported fork of the MySQL relational database management system, intended to remain free and open-source software under the GNU General Public License. Development is led by some of the original developers of MySQL, who forked it due to concerns over its acquisition by Oracle Corporation. MariaDB intends to maintain high compatibility with MySQL, ensuring a drop-in replacement capability with library binary parity and exact matching with MySQL APIs and commands, it includes a new storage engine, Aria, an alternative to MyISAM that intends to be the default transactional and non-transactional engine. It used XtraDB as the default storage engine, switched back to InnoDB since version 10.2. Its lead developer is Michael "Monty" Widenius, one of the founders of MySQL AB and the founder of Monty Program AB. On 16 January 2008, MySQL AB announced that it had agreed to be acquired by Sun Microsystems for $1 billion; the acquisition completed on 26 February 2008.
MariaDB is named after Monty's younger daughter Maria, similar to how MySQL is named after his other daughter My. MariaDB version numbers follow the MySQL's numbering scheme up to version 5.5. Thus, MariaDB 5.5 offers all of the MySQL 5.5 features. There exists a gap in MySQL versions between 5.1 and 5.5, while MariaDB issued 5.2 and 5.3 point releases. Since specific new features have been developed in MariaDB, the developers decided that a major version number change was necessary. MariaDB has been supported in Amazon RDS service since October 2015. MariaDB is a supported database in Microsoft Azure. MariaDB's API and protocol are compatible with those used by MySQL, plus some features to support native non-blocking operations and progress reporting; this means that all connectors and applications which work with MySQL should work on MariaDB—whether or not they support its native features. On this basis, Fedora developers replaced MySQL with MariaDB in Fedora 19, out of concerns that Oracle was making MySQL a more closed software project.
OpenBSD in April 2013 dropped MySQL for MariaDB 5.5. In December 2012 Michael Widenius, David Axmark, Allan Larsson announced the formation of a foundation that would oversee the development of MariaDB. In April 2013 the Foundation announced that it had appointed Simon Phipps as its Secretary and interim Chief Executive Officer, Rasmus Johansson as Chairman of the Board, Andrew Katz, Jeremy Zawodny, Michael Widenius as Board members. Noting that it wished to create a governance model similar to that used by the Eclipse Foundation, the Board appointed the Eclipse Foundation's Executive Director Mike Milinkovich as an advisor to lead the transition. SkySQL Corporation Ab, a company formed by ex-MySQL executives and investors after Oracle bought MySQL, announced in April 2013 that they were merging their company with Monty Program AB, joining the MariaDB Foundation; the MariaDB Foundation appointed Widenius as its CTO. Simon Phipps quit in 2014 on the sale of the MariaDB trademark to SkySQL, he said: "I quit as soon as it was obvious the company was not going to allow an independent foundation."
On 1 October 2014, SkySQL Corporation AB changed its name to MariaDB Corporation AB to reflect its role as the main driving force behind the development of MariaDB server and the biggest support-provider for it. MariaDB is a registered trademark of MariaDB Corporation AB, used under license by the MariaDB Foundation. From January 2015 to September 2018, Otto Kekäläinen was the CEO of the MariaDB Foundation, he stepped down on 1 October of that year. Arjen Lentz was appointed CEO of the Foundation in October 2018, but resigned in December 2018. Kaj Arnö joined as the CEO on 1 February 2019. Eric Herman is the current Chairman of the Board. MariaDB is used at ServiceNow, DBS Bank, Google and the Wikimedia Foundation since 2013. Several Linux and BSD distributions include MariaDB, like Ubuntu; some default to MariaDB, such as Arch Linux, Debian, Red Hat Enterprise Linux, CentOS, openSUSE, SUSE Linux Enterprise Server, OpenBSD, FreeBSD. In 2013 Google tasked one of its engineers to work at the MariaDB Foundation.
A group of investment companies led by Intel has invested $20 million in SkySQL. The European Investment Bank has funded MariaDB with €25 million in 2017. Comparison of relational database management systems Multi-master replication Bartholomew, Daniel. Getting Started with MariaDB. ISBN 9781782168096. Bartholomew, Daniel. MariaDB Cookbook. ISBN 978-1-78328-440-5. Forta, Ben. MariaDB Crash Course. Addison Wesley. ISBN 0-321-79994-1. MariaDB Foundation website MariaDB Corporation website MariaDB, the Backward Compatible Branch of MySQL Database Server on YouTube – a lecture given by Monty Widenius at Google
Elasticsearch is a search engine based on the Lucene library. It provides a distributed, multitenant-capable full-text search engine with an HTTP web interface and schema-free JSON documents. Elasticsearch is developed in Java. Following an open-core business model, parts of the software are licensed under various open source licenses, while other parts fall under the commercial Elastic License. Official clients are available in Java. NET, PHP, Apache Groovy and many other languages. According to the DB-Engines ranking, Elasticsearch is the most popular enterprise search engine followed by Apache Solr based on Lucene. Shay Banon created the precursor to Elasticsearch, called Compass, in 2004. While thinking about the third version of Compass he realized that it would be necessary to rewrite big parts of Compass to "create a scalable search solution". So he created "a solution built from the ground up to be distributed" and used a common interface, JSON over HTTP, suitable for programming languages other than Java as well.
Shay Banon released the first version of Elasticsearch in February 2010. Elastic NV was founded in 2012 to provide commercial services and products around Elasticsearch and related software. In June 2014, the company announced raising $70 million in a Series C funding round, just 18 months after forming the company; the round was led by New Enterprise Associates. Additional funders include Index Ventures; this round brings total funding to $104M. In March 2015, the company Elasticsearch changed their name to Elastic. In June 2018, Elastic filed for an initial public offering with a estimated valuation of between 1.5 and 3 billion dollars. On 5 October 2018, Elastic was listed on the New York Stock Exchange. Elasticsearch can be used to search all kinds of documents, it provides scalable search, has near real-time search, supports multitenancy. "Elasticsearch is distributed, which means that indices can be divided into shards and each shard can have zero or more replicas. Each node hosts one or more shards, acts as a coordinator to delegate operations to the correct shard.
Rebalancing and routing are done automatically". Related data is stored in the same index, which consists of one or more primary shards, zero or more replica shards. Once an index has been created, the number of primary shards cannot be changed. Elasticsearch is developed alongside a data collection and log-parsing engine called Logstash, an analytics and visualisation platform called Kibana, Beats, a collection of lightweight data shippers; the four products are designed for use as an integrated solution, referred to as the "Elastic Stack". Elasticsearch uses Lucene and tries to make all its features available through the JSON and Java API, it supports facetting and percolating, which can be useful for notifying if new documents match for registered queries. Another feature handles the long-term persistence of the index. Elasticsearch supports real-time GET requests, which makes it suitable as a NoSQL datastore, but it lacks distributed transactions. Developed from the Found acquisition by Elastic in 2015, Elastic Cloud is a family of Elasticsearch-powered SaaS offerings which include the Elasticsearch Service, as well as Elastic App Search Service, Elastic Site Search Service which were developed from Elastic’s acquisition of Swiftype.
In late 2017, Elastic formed partnerships with Google to offer Elastic Cloud in GCP, Alibaba to offer Elasticsearch and Kibana in Alibaba Cloud. Elasticsearch Service on Elastic Cloud is the official hosted and managed Elasticsearch and Kibana offering from the creators of the project since August 2018 Elasticsearch Service users can create secure deployments with partners, Google Cloud Platform and Alibaba Cloud. AWS offers Elasticsearch as a managed service since 2015; such managed services provide hosting, deployment and other support. Most managed services include support for Kibana. Elasticsearch is the basis of Pangeanic's contribution to the EU's Marie Curie research project "EXPERT" called ActivaTM. Pangeanic built a bilingual database compatible with Computer-Assisted Translation tools, which could offer real-time access via API from a variety of tools; the project received further funding from the EU as the National and European Central Translation Memory project under the Connecting Europe Facility programme.
NEC TM aims to centralise national translation assets in all the EU's Member States so countries can re-use bilingual translation data produced as a result of public procurement contracts. 2018-11-15 AWS Elasticsearch database belonging to VoxOx exposed tens of millions of text messages, including password reset links, two-factor codes, shipping notifications and more. 2018-11-27 Elasticsearch database belonging to Urban Massage exposed more than 309,000 user records, including names, email addresses and phone numbers. 2019-01-21 Elasticsearch database belonging to Youth-run agency AIESEC exposed over 4 million intern applications including the applicant’s name, date of birth, the reasons why the person was applying for the internship. 2019-01-12 Elasticsearch server belonging to do-it-yourself chain, B&Q exposed personal details of individuals caught or suspected of stealing goods from stores. 2019-01-23 Elasticsearch database belonging to Ascension Data and Analytics exposed 24 million financial and banking documents, representing tens of thousands of loans and mortgages from some of the biggest banks in the U.
S. List of information retrieval libraries Information extraction Official website
MySQL is an open-source relational database management system. Its name is a combination of "My", the name of co-founder Michael Widenius's daughter, "SQL", the abbreviation for Structured Query Language. MySQL is free and open-source software under the terms of the GNU General Public License, is available under a variety of proprietary licenses. MySQL was owned and sponsored by the Swedish company MySQL AB, bought by Sun Microsystems. In 2010, when Oracle acquired Sun, Widenius forked the open-source MySQL project to create MariaDB. MySQL is a component of the LAMP web application software stack, an acronym for Linux, Apache, MySQL, Perl/PHP/Python. MySQL is used by many database-driven web applications, including Drupal, phpBB, WordPress. MySQL is used by many popular websites, including Facebook, Twitter and YouTube. MySQL is written in C and C++, its SQL parser is written in yacc. MySQL works on many system platforms, including AIX, BSDi, FreeBSD, HP-UX, eComStation, i5/OS, IRIX, macOS, Microsoft Windows, NetBSD, Novell NetWare, OpenBSD, OpenSolaris, OS/2 Warp, QNX, Oracle Solaris, SunOS, SCO OpenServer, SCO UnixWare and Tru64.
A port of MySQL to OpenVMS exists. The MySQL server software itself and the client libraries use dual-licensing distribution, they are offered under a proprietary license. Support can be obtained from the official manual. Free support additionally is available in different IRC forums. Oracle offers paid support via its MySQL Enterprise products, they differ in price. Additionally, a number of third party organisations exist to provide support and services, including MariaDB and Percona. MySQL has received positive reviews, reviewers noticed it "performs well in the average case" and that the "developer interfaces are there, the documentation is very good", it has been tested to be a "fast and true multi-user, multi-threaded sql database server". MySQL was created by a Swedish company, MySQL AB, founded by David Axmark, Allan Larsson and Michael "Monty" Widenius. Original development of MySQL by Widenius and Axmark began in 1994; the first version of MySQL appeared on 23 May 1995. It was created for personal usage from mSQL based on the low-level language ISAM, which the creators considered too slow and inflexible.
They created a new SQL interface, while keeping the same API as mSQL. By keeping the API consistent with the mSQL system, many developers were able to use MySQL instead of the mSQL antecedent. Additional milestones in MySQL development included: First internal release on 23 May 1995 Version 3.19: End of 1996, from www.tcx.se Version 3.20: January 1997 Windows version was released on 8 January 1998 for Windows 95 and NT Version 3.21: production release 1998, from www.mysql.com Version 3.22: alpha, beta from 1998 Version 3.23: beta from June 2000, production release 22 January 2001 Version 4.0: beta from August 2002, production release March 2003. Version 4.01: beta from August 2003, Jyoti adopts MySQL for database tracking Version 4.1: beta from June 2004, production release October 2004. Version 5.0: beta from March 2005, production release October 2005. The developer of the Federated Storage Engine states that "The Federated Storage Engine is a proof-of-concept storage engine", but the main distributions of MySQL version 5.0 included it and turned it on by default.
Documentation of some of the short-comings appears in "MySQL Federated Tables: The Missing Manual". Sun Microsystems acquired MySQL AB in 2008. Version 5.1: production release 27 November 2008 Version 5.1 contained 20 known crashing and wrong result bugs in addition to the 35 present in version 5.0. MySQL 5.1 and 6.0-alpha showed poor performance when used for data warehousing – due to its inability to utilize multiple CPU cores for processing a single query. Oracle acquired Sun Microsystems on 27 January 2010; the day Oracle announced the purchase of Sun, Michael "Monty" Widenius forked MySQL, launching MariaDB, took a swath of MySQL developers with him. MySQL Server 5.5 was available. Enhancements and features include: The default storage engine is InnoDB, which supports transactions and referential integrity constraints. Improved InnoDB I/O subsystem Improved SMP support Semisynchronous replication. SIGNAL and RESIGNAL statement in compliance with the SQL standard. Support for supplementary Unicode character sets utf16, utf32, utf8mb4.
New options for user-defined partitioning. MySQL Server 6.0.11-alpha was announced on 22 May 2009 as the last release of the 6.0 line. Future MySQL Server development uses a New Release Model. Features developed for 6.0 are being incorporated into future releases. The general availability of MySQL 5.6 was announced in February 2013. New features included performance improvements to the query optimizer, higher transactional throughput in InnoDB, new NoSQL-style memcached APIs, improvements to partitioning for querying and managing large tables, TIMESTAMP column type that stores milliseconds, improvements to replication, better performance monitoring by expanding the data available through the PERFORMANCE_SCHEMA; the InnoDB storage engine included support for full-text search and improved group commit performance. The general availability of MySQL 5.7 was a
GNU General Public License
The GNU General Public License is a widely-used free software license, which guarantees end users the freedom to run, study and modify the software. The license was written by Richard Stallman of the Free Software Foundation for the GNU Project, grants the recipients of a computer program the rights of the Free Software Definition; the GPL is a copyleft license, which means that derivative work can only be distributed under the same license terms. This is in distinction to permissive free software licenses, of which the BSD licenses and the MIT License are widely-used examples. GPL was the first copyleft license for general use; the GPL license family has been one of the most popular software licenses in the free and open-source software domain. Prominent free-software programs licensed under the GPL include the Linux kernel and the GNU Compiler Collection. David A. Wheeler argues that the copyleft provided by the GPL was crucial to the success of Linux-based systems, giving the programmers who contributed to the kernel the assurance that their work would benefit the whole world and remain free, rather than being exploited by software companies that would not have to give anything back to the community.
In 2007, the third version of the license was released to address some perceived problems with the second version that were discovered during its long-time usage. To keep the license up to date, the GPL license includes an optional "any version" clause, allowing users to choose between the original terms or the terms in new versions as updated by the FSF. Developers can omit it; the GPL was written by Richard Stallman in 1989, for use with programs released as part of the GNU project. The original GPL was based on a unification of similar licenses used for early versions of GNU Emacs, the GNU Debugger and the GNU C Compiler; these licenses contained similar provisions to the modern GPL, but were specific to each program, rendering them incompatible, despite being the same license. Stallman's goal was to produce one license that could be used for any project, thus making it possible for many projects to share code; the second version of the license, version 2, was released in 1991. Over the following 15 years, members of the free software community became concerned over problems in the GPLv2 license that could let someone exploit GPL-licensed software in ways contrary to the license's intent.
These problems included tivoization, compatibility issues similar to those of the Affero General Public License—and patent deals between Microsoft and distributors of free and open-source software, which some viewed as an attempt to use patents as a weapon against the free software community. Version 3 was developed to attempt to address these concerns and was released on 29 June 2007. Version 1 of the GNU GPL, released on 25 February 1989, prevented what were the two main ways that software distributors restricted the freedoms that define free software; the first problem was that distributors may publish binary files only—executable, but not readable or modifiable by humans. To prevent this, GPLv1 stated that copying and distributing copies or any portion of the program must make the human-readable source code available under the same licensing terms; the second problem was that distributors might add restrictions, either to the license, or by combining the software with other software that had other restrictions on distribution.
The union of two sets of restrictions would apply to the combined work, thus adding unacceptable restrictions. To prevent this, GPLv1 stated that modified versions, as a whole, had to be distributed under the terms in GPLv1. Therefore, software distributed under the terms of GPLv1 could be combined with software under more permissive terms, as this would not change the terms under which the whole could be distributed. However, software distributed under GPLv1 could not be combined with software distributed under a more restrictive license, as this would conflict with the requirement that the whole be distributable under the terms of GPLv1. According to Richard Stallman, the major change in GPLv2 was the "Liberty or Death" clause, as he calls it – Section 7; the section says that licensees may distribute a GPL-covered work only if they can satisfy all of the license's obligations, despite any other legal obligations they might have. In other words, the obligations of the license may not be severed due to conflicting obligations.
This provision is intended to discourage any party from using a patent infringement claim or other litigation to impair users' freedom under the license. By 1990, it was becoming apparent that a less restrictive license would be strategically useful for the C library and for software libraries that did the job of existing proprietary ones; the version numbers diverged in 1999 when version 2.1 of the LGPL was released, which renamed it the GNU Lesser General Public License to reflect its place in the philosophy. Most "GPLv2 or any version" is stated by users of the license, to allow upgrading to GPLv3. In late 2005, the Free Software Foundation announced work on version 3 of the GPL. On 16 January 2006, the first "discussion draft" of GPLv3 was published, the public consultation began; the public consultation was planned for ni
In mathematics and computing, hexadecimal is a positional numeral system with a radix, or base, of 16. It uses sixteen distinct symbols, most the symbols "0"–"9" to represent values zero to nine, "A"–"F" to represent values ten to fifteen. Hexadecimal numerals are used by computer system designers and programmers, as they provide a more human-friendly representation of binary-coded values; each hexadecimal digit represents four binary digits known as a nibble, half a byte. For example, a single byte can have values ranging from 0000 0000 to 1111 1111 in binary form, which can be more conveniently represented as 00 to FF in hexadecimal. In mathematics, a subscript is used to specify the radix. For example the decimal value 10,995 would be expressed in hexadecimal as 2AF316. In programming, a number of notations are used to support hexadecimal representation involving a prefix or suffix; the prefix 0x is used in C and related languages, which would denote this value by 0x2AF3. Hexadecimal is used in the transfer encoding Base16, in which each byte of the plaintext is broken into two 4-bit values and represented by two hexadecimal digits.
In contexts where the base is not clear, hexadecimal numbers can be ambiguous and confused with numbers expressed in other bases. There are several conventions for expressing values unambiguously. A numerical subscript can give the base explicitly: 15910 is decimal 159; some authors prefer a text subscript, such as 159decimal and 159hex, or 159h. In linear text systems, such as those used in most computer programming environments, a variety of methods have arisen: In URIs, character codes are written as hexadecimal pairs prefixed with %: http://www.example.com/name%20with%20spaces where %20 is the space character, ASCII code point 20 in hex, 32 in decimal. In XML and XHTML, characters can be expressed as hexadecimal numeric character references using the notation
ode, thus ’. In the Unicode standard, a character value is represented with U+ followed by the hex value, e.g. U+20AC is the Euro sign. Color references in HTML, CSS and X Window can be expressed with six hexadecimal digits prefixed with #: white, for example, is represented #FFFFFF.
CSS allows 3-hexdigit abbreviations with one hexdigit per component: #FA3 abbreviates #FFAA33. Unix shells, AT&T assembly language and the C programming language use the prefix 0x for numeric constants represented in hex: 0x5A3. Character and string constants may express character codes in hexadecimal with the prefix \x followed by two hex digits:'\x1B' represents the Esc control character. To output an integer as hexadecimal with the printf function family, the format conversion code %X or %x is used. In MIME quoted-printable encoding, characters that cannot be represented as literal ASCII characters are represented by their codes as two hexadecimal digits prefixed by an equal to sign =, as in Espa=F1a to send "España". In Intel-derived assembly languages and Modula-2, hexadecimal is denoted with a suffixed H or h: FFh or 05A3H; some implementations require a leading zero when the first hexadecimal digit character is not a decimal digit, so one would write 0FFh instead of FFh Other assembly languages, Delphi, some versions of BASIC, GameMaker Language and Forth use $ as a prefix: $5A3.
Some assembly languages use the notation H'ABCD'. Fortran 95 uses Z'ABCD'. Ada and VHDL enclose hexadecimal numerals in based "numeric quotes": 16#5A3#. For bit vector constants VHDL uses the notation x"5A3". Verilog represents hexadecimal constants in the form 8'hFF, where 8 is the number of bits in the value and FF is the hexadecimal constant; the Smalltalk language uses the prefix 16r: 16r5A3 PostScript and the Bourne shell and its derivatives denote hex with prefix 16#: 16#5A3. For PostScript, binary data can be expressed as unprefixed consecutive hexadecimal pairs: AA213FD51B3801043FBC... Common Lisp uses the prefixes # 16r. Setting the variables *read-base* and *print-base* to 16 can be used to switch the reader and printer of a Common Lisp system to Hexadecimal number representation for reading and printing numbers, thus Hexadecimal numbers can be represented without the #x or #16r prefix code, when the input or output base has been changed to 16. MSX BASIC, QuickBASIC, FreeBASIC and Visual Basic prefix hexadecimal numbers with &H: &H5A3 BBC BASIC and Locomotive BASIC use & for hex.
TI-89 and 92 series uses a 0h prefix: 0h5A3 ALGOL 68 uses the prefix 16r to denote hexadecimal numbers: 16r5a3. Binary and octal numbers can be specified similarly; the most common format for hexadecimal on IBM mainframes and midrange computers running the traditional OS's is X'5A3', is used in Assembler, PL/I, COBOL, JCL, scripts and other places. This format was common on
A computer network is a digital telecommunications network which allows nodes to share resources. In computer networks, computing devices exchange data with each other using connections between nodes; these data links are established over cable media such as wires or optic cables, or wireless media such as Wi-Fi. Network computer devices that originate and terminate the data are called network nodes. Nodes are identified by network addresses, can include hosts such as personal computers and servers, as well as networking hardware such as routers and switches. Two such devices can be said to be networked together when one device is able to exchange information with the other device, whether or not they have a direct connection to each other. In most cases, application-specific communications protocols are layered over other more general communications protocols; this formidable collection of information technology requires skilled network management to keep it all running reliably. Computer networks support an enormous number of applications and services such as access to the World Wide Web, digital video, digital audio, shared use of application and storage servers and fax machines, use of email and instant messaging applications as well as many others.
Computer networks differ in the transmission medium used to carry their signals, communications protocols to organize network traffic, the network's size, traffic control mechanism and organizational intent. The best-known computer network is the Internet; the chronology of significant computer-network developments includes: In the late 1950s, early networks of computers included the U. S. military radar system Semi-Automatic Ground Environment. In 1959, Anatolii Ivanovich Kitov proposed to the Central Committee of the Communist Party of the Soviet Union a detailed plan for the re-organisation of the control of the Soviet armed forces and of the Soviet economy on the basis of a network of computing centres, the OGAS. In 1960, the commercial airline reservation system semi-automatic business research environment went online with two connected mainframes. In 1963, J. C. R. Licklider sent a memorandum to office colleagues discussing the concept of the "Intergalactic Computer Network", a computer network intended to allow general communications among computer users.
In 1964, researchers at Dartmouth College developed the Dartmouth Time Sharing System for distributed users of large computer systems. The same year, at Massachusetts Institute of Technology, a research group supported by General Electric and Bell Labs used a computer to route and manage telephone connections. Throughout the 1960s, Paul Baran and Donald Davies independently developed the concept of packet switching to transfer information between computers over a network. Davies pioneered the implementation of the concept with the NPL network, a local area network at the National Physical Laboratory using a line speed of 768 kbit/s. In 1965, Western Electric introduced the first used telephone switch that implemented true computer control. In 1966, Thomas Marill and Lawrence G. Roberts published a paper on an experimental wide area network for computer time sharing. In 1969, the first four nodes of the ARPANET were connected using 50 kbit/s circuits between the University of California at Los Angeles, the Stanford Research Institute, the University of California at Santa Barbara, the University of Utah.
Leonard Kleinrock carried out theoretical work to model the performance of packet-switched networks, which underpinned the development of the ARPANET. His theoretical work on hierarchical routing in the late 1970s with student Farouk Kamoun remains critical to the operation of the Internet today. In 1972, commercial services using X.25 were deployed, used as an underlying infrastructure for expanding TCP/IP networks. In 1973, the French CYCLADES network was the first to make the hosts responsible for the reliable delivery of data, rather than this being a centralized service of the network itself. In 1973, Robert Metcalfe wrote a formal memo at Xerox PARC describing Ethernet, a networking system, based on the Aloha network, developed in the 1960s by Norman Abramson and colleagues at the University of Hawaii. In July 1976, Robert Metcalfe and David Boggs published their paper "Ethernet: Distributed Packet Switching for Local Computer Networks" and collaborated on several patents received in 1977 and 1978.
In 1979, Robert Metcalfe pursued making Ethernet an open standard. In 1976, John Murphy of Datapoint Corporation created ARCNET, a token-passing network first used to share storage devices. In 1995, the transmission speed capacity for Ethernet increased from 10 Mbit/s to 100 Mbit/s. By 1998, Ethernet supported transmission speeds of a Gigabit. Subsequently, higher speeds of up to 400 Gbit/s were added; the ability of Ethernet to scale is a contributing factor to its continued use. Computer networking may be considered a branch of electrical engineering, electronics engineering, telecommunications, computer science, information technology or computer engineering, since it relies upon the theoretical and practical application of the related disciplines. A computer network facilitates interpersonal communications allowing users to communicate efficiently and via various means: email, instant messaging, online chat, video telephone calls, video conferencing. A network allows sharing of computing resources.
Users may access and use resources provided by devices on the network, such as printing a document on a shared network printer or use of a shared storage device. A network allows sharing of files, and