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Communications Protocol
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. The protocol defines the rules, syntax, semantics and synchronization of communication and possible error recovery methods. Protocols may be implemented by hardware, software, or a combination of both. Communicating systems use well-defined formats for exchanging various messages. Each message has an exact meaning intended to elicit a response from a range of possible responses pre-determined for that particular situation. The specified behavior is typically independent of how it is to be implemented. Communication protocols have to be agreed upon by the parties involved. To reach an agreement, a protocol may be developed into a technical standard. A programming language describes the same for computations, so there is a close analogy between protocols and programming languages: ''protocols ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communications System
A communications system or communication system is a collection of individual telecommunications networks, transmission systems, relay stations, tributary stations, and terminal equipment usually capable of interconnection and interoperation to form an integrated whole. The components of a communications system serve a common purpose, are technically compatible, use common procedures, respond to controls, and operate in union. Telecommunications is a method of communication (e.g., for sports broadcasting, mass media, journalism, etc.). Communication is the act of conveying intended meanings from one entity or group to another through the use of mutually understood signs and semiotic rules. Types By media An optical communication system is any form of telecommunication that uses light as the transmission medium. Equipment consists of a transmitter, which encodes a ''message'' into an optical ''signal'', a ''communication channel'', which carries the signal to its dest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocol Stack
The protocol stack or network stack is an implementation of a computer networking protocol suite or protocol family. Some of these terms are used interchangeably but strictly speaking, the ''suite'' is the definition of the communication protocols, and the ''stack'' is the software implementation of them. Individual protocols within a suite are often designed with a single purpose in mind. This modularization simplifies design and evaluation. Because each protocol module usually communicates with two others, they are commonly imagined as layers in a stack of protocols. The lowest protocol always deals with low-level interaction with the communications hardware. Each higher layer adds additional capabilities. User applications usually deal only with the topmost layers. General protocol suite description T ~ ~ ~ T ____ Imagine three computers: ''A'', ''B'', and ''C''. ''A'' and ''B'' both have radio equipment and can communicate via the airwaves using a suitable networ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Control Protocol (ARPANET)
The Network Control Protocol (NCP) was a communication protocol for a computer network in the 1970s and early 1980s. It provided the middle layers of the protocol stack running on host computers of the ARPANET, the predecessor to the modern Internet. NCP preceded the Transmission Control Protocol (TCP) as a transport layer protocol used during the early ARPANET. NCP was a simplex protocol that utilized two port addresses, establishing two connections, for two-way communications. An odd and an even port were reserved for each application layer application or protocol. The standardization of TCP and UDP reduced the need for the use of two simplex ports for each application down to one duplex port. There is some confusion over the name, even among the engineers who worked with the ARPANET. Originally, there was no need for a name for the protocol stack as a whole, so none existed. When the development of TCP started, a name was required for its predecessor, and the pre-existing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bolt Beranek And Newman
Raytheon BBN (originally Bolt Beranek and Newman Inc.) is an American research and development company, based next to Fresh Pond in Cambridge, Massachusetts, United States. In 1966, the Franklin Institute awarded the firm the Frank P. Brown Medal, in 1999 BBN received the IEEE Corporate Innovation Recognition, and on 1 February 2013, BBN was awarded the National Medal of Technology and Innovation, the highest honors that the U.S. government bestows upon scientists, engineers and inventors, by President Barack Obama. It became a wholly owned subsidiary of Raytheon in 2009. History BBN has its roots in an initial partnership formed on 15 October 1948 between Leo Beranek and Richard Bolt, professors at the Massachusetts Institute of Technology. Bolt had won a commission to be an acoustic consultant for the new United Nations permanent headquarters to be built in New York City. Realizing the magnitude of the project at hand, Bolt had pulled in his MIT colleague Beranek for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBN Report 1822
The Interface Message Processor (IMP) was the packet switching node used to interconnect participant networks to the ARPANET from the late 1960s to 1989. It was the first generation of gateways, which are known today as routers. An IMP was a ruggedized Honeywell DDP-516 minicomputer with special-purpose interfaces and software. In later years the IMPs were made from the non-ruggedized Honeywell 316 which could handle two-thirds of the communication traffic at approximately one-half the cost. An IMP requires the connection to a host computer via a special bit- serial interface, defined in ''BBN Report 1822''. The IMP software and the ARPA network communications protocol running on the IMPs was discussed in , the first of a series of standardization documents published by what later became the Internet Engineering Task Force (IETF). History The concept of an "Interface computer" was first proposed in 1966 by Donald Davies for the NPL network in England. The same idea was ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARPANET
The Advanced Research Projects Agency Network (ARPANET) was the first wide-area packet-switched network with distributed control and one of the first networks to implement the TCP/IP protocol suite. Both technologies became the technical foundation of the Internet. The ARPANET was established by the Advanced Research Projects Agency (ARPA) of the United States Department of Defense. Building on the ideas of J. C. R. Licklider, Bob Taylor initiated the ARPANET project in 1966 to enable access to remote computers. Taylor appointed Larry Roberts as program manager. Roberts made the key decisions about the network design. He incorporated Donald Davies' concepts and designs for packet switching, and sought input from Paul Baran. ARPA awarded the contract to build the network to Bolt Beranek & Newman who developed the first protocol for the network. Roberts engaged Leonard Kleinrock at UCLA to develop mathematical methods for analyzing the packet network technology. The first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roger Scantlebury
Roger Anthony Scantlebury (born August 1936) is a British computer scientist who worked at the National Physical Laboratory (NPL) and later at Logica. Scantlebury participated in pioneering work to develop packet switching and associated communication protocols at the NPL in the late 1960s. He proposed the use of the technology in the ARPANET, the forerunner of the Internet, at the inaugural Symposium on Operating Systems Principles in 1967. During the 1970s, he was an active member of international working groups that developed concepts for the interconnection of computer networks. Early life Roger Scantlebury was born in Ealing in 1936. Career National Physical Laboratory Scantlebury worked at the National Physical Laboratory in south-west London, in collaboration with the National Research Development Corporation (NRDC). His early work was on the Automatic Computing Engine and English Electric DEUCE computers. Following this he worked with Donald Davies on his pioneering p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NPL Data Communications Network
The NPL network, or NPL Data Communications Network, was a local area computer network operated by a team from the National Physical Laboratory in London that pioneered the concept of packet switching. Based on designs first conceived by Donald Davies in 1965, development work began in 1968. Elements of the first version of the network, the Mark I, became operational during 1969 then fully operational in January 1970, and the Mark II version operated from 1973 until 1986. The NPL network and the ARPANET in the United States were the first two computer networks that implemented packet switching and the NPL network was the first to use high-speed links. Origins In 1965, Donald Davies, who was later appointed to head of the NPL Division of Computer Science, proposed a commercial national data network based on packet switching in ''Proposal for the Development of a National Communications Service for On-line Data Processing''. After the proposal was not taken up nationally, during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technological Convergence
Technological convergence is the tendency for technologies that were originally unrelated to become more closely integrated and even unified as they develop and advance. For example, watches, telephones, television, computers, and social media platforms began as separate and mostly unrelated technologies, but have converged in many ways into an interrelated telecommunication, media, and technology industry. Definitions "Convergence is a deep integration of knowledge, tools, and all relevant activities of human activity for a common goal, to allow society to answer new questions to change the respective physical or social ecosystem. Such changes in the respective ecosystem open new trends, pathways, and opportunities in the following divergent phase of the process" (Roco 2002, Bainbridge and Roco 2016). Siddhartha Menon defines convergence as integration and digitalization. Integration, here, is defined as "a process of transformation measure by the degree to which diverse media ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public Switched Telephone Network
The public switched telephone network (PSTN) provides Communications infrastructure, infrastructure and services for public Telecommunications, telecommunication. The PSTN is the aggregate of the world's circuit-switched telephone networks that are operated by national, regional, or local telephony operators. These consist of telephone lines, fiber optic cables, microwave transmission links, Routing in cellular networks, cellular networks, communications satellites, and undersea telephone cables, all interconnected by switching centers which allow most telephones to communicate with each other. Originally a network of fixed-line Analog signal processing, analog telephone systems, the PSTN is now almost entirely digital in its core network and includes mobile and other networks, as well as fixed telephones. The technical operation of the PSTN adheres to the standards created by the ITU-T. These standards allow different networks in different countries to interconnect seamlessly. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as coded drumb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU-T
The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors (divisions or units) of the International Telecommunication Union (ITU). It is responsible for coordinating standards for telecommunications and Information Communication Technology such as X.509 for cybersecurity, Y.3172 and Y.3173 for machine learning, and H.264/MPEG-4 AVC for video compression, between its Member States, Private Sector Members, and Academia Members. The first meeting of the World Telecommunication Standardization Assembly (WTSA), the sector's governing conference, took place on 1 March of that year. ITU-T has a permanent secretariat called the Telecommunication Standardization Bureau (TSB), which is based at the ITU headquarters in Geneva, Switzerland. The current director of the TSB is Chaesub Lee (of South Korea), whose first 4-year term commenced on 1 January 2015, and whose second 4-year term commenced on 1 January 2019. Chaesub Lee succeeded Malcolm Johnson (Director), Malc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
