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Terrestrial Wideband Network
{{more footnotes, date=June 2019 The Terrestrial Wideband Network was a DARPA-sponsored experimental network designed to support research in high-speed networking protocols and distributed multimedia applications. It was built and operated by BBN Technologies from May 1989 to about 1991; although originally planned to turn into the Defense Research Internet, it instead evolved into the Defense Simulation Internet. The Terrestrial Wideband Network was a trans-continental network implemented via Wideband Packet Switches (based on BBN Butterfly parallel computers) connected by T1 circuits. It replaced the 3 megabit/second Satellite Wideband Network, which had been in operation for the previous 8 years. Because it was based on a single cross-country T1 trunk from the DARPA National Networking Testbed (NNT), the Terrestrial Wideband Network's topology was linear, i.e., a series of packet switches connected in a line by T1 trunks. Each T1 link ran at 1.544 megabits per second. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DARPA
The Defense Advanced Research Projects Agency (DARPA) is a research and development agency of the United States Department of Defense responsible for the development of emerging technologies for use by the military. Originally known as the Advanced Research Projects Agency (ARPA), the agency was created on February 7, 1958, by President Dwight D. Eisenhower in response to the Soviet Union, Soviet launching of Sputnik 1 in 1957. By collaborating with academia, industry, and government partners, DARPA formulates and executes research and development projects to expand the frontiers of technology and science, often beyond immediate U.S. military requirements.Dwight D. Eisenhower and Science & Technology, (2008). Dwight D. Eisenhower Memorial CommissionSource ''The Economist'' has called DARPA the agency "that shaped the modern world," and pointed out that "Moderna COVID-19 vaccine, Moderna's COVID-19 vaccine sits alongside weather satellites, Global Positioning System, GPS, Unmann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBN Technologies
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 h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Defense Simulation Internet
{{more footnotes, date=June 2019 The Defense Simulation Internet (DSI) was a specialized, wide-area network created to support Distributed Interactive Simulation and videoconferences. It was sponsored by DARPA, and built and operated by BBN Technologies from about 1991-1995, after which time it was operated by the Defense Information Systems Agency (DISA). The DSI evolved from DARPA's earlier Terrestrial Wideband Network, which could provide the realtime multicast with bandwidth guarantees that are essential to distributed interactive simulations via the Internet Stream Protocol (ST-II). A Defense Science Board study in 1993 highlighted the importance of these capabilities in simulations, and by late 1994, the DSI connected about 100 local area networks at sites around the world. Many links operated at multiple T1 circuits, for an aggregate bandwidth of about 6 megabits/second. In 1994, DSI program management transitioned to a joint program office of DARPA and DISA, and after the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBN Butterfly
The BBN Butterfly was a massively parallel computer built by Bolt, Beranek and Newman in the 1980s. It was named for the "butterfly" multi-stage switching network around which it was built. Each machine had up to 512 CPUs, each with local memory, which could be connected to allow every CPU access to every other CPU's memory, although with a substantially greater latency (roughly 15:1) than for its own. The CPUs were commodity microprocessors. The memory address space was shared. The first generation used Motorola 68000 processors, followed by a 68010 version. The Butterfly connect was developed specifically for this computer. The second or third generation, GP-1000 models used Motorola 68020's and scaled to 256 CPUs. The later, TC-2000 models used Motorola MC88100's, and scaled to 512 CPUs. The Butterfly was initially developed as the Voice Funnel, a router for the ST-II protocol intended for carrying voice and video over IP networks. The Butterfly hardware was later used for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T-carrier
The T-carrier is a member of the series of carrier systems developed by AT&T Bell Laboratories for digital transmission of multiplexed telephone calls. The first version, the Transmission System 1 (T1), was introduced in 1962 in the Bell System, and could transmit up to 24 telephone calls simultaneously over a single transmission line of copper wire. Subsequent specifications carried multiples of the basic T1 (1.544 Mbit/s) data rates, such as T2 (6.312 Mbit/s) with 96 channels, T3 (44.736 Mbit/s) with 672 channels, and others. Although a ''T2'' was defined as part of AT&T's T-carrier system, which defined five levels, T1 through T5, only the T1 and T3 were commonly in use.1999 ad: On the left, in an aisle seat, a man who very much "filled" his airline seat while on the right side of the aisle is a height-challenged man whose shoe toes barely reach the floor Transmission System 1 The T-carrier is a hardware specification for carrying multiple time-division mul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Protocol
The Internet Protocol (IP) is the network layer communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. IP has the task of delivering packets from the source host to the destination host solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram with source and destination information. IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, which was complemented by a connection-oriented service that became the basis for the Transmission Control Protocol (TCP). The Internet protocol suite is therefore often referred to as ''TCP/IP''. The first major version of IP, Internet Protocol Version 4 (IPv4), is the do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Stream Protocol
The Internet Stream Protocol (ST) is a family of experimental protocols first defined in Internet Experiment Note IEN-119 in 1979, and later substantially revised in RFC 1190 (ST-II) and RFC 1819 (ST2+). The protocol uses the version number 5 in the version field of the Internet Protocol header, but was never known as IPv5. The successor to IPv4 was thus named IPv6 to eliminate any possible confusion about the actual protocol in use. History The Internet Stream Protocol family was never introduced for public use, but many of the concepts available in ST are similar to later Asynchronous Transfer Mode protocols and can be found in Multiprotocol Label Switching (MPLS). They also presaged voice over IP. ST arose as the transport protocol of the Network Voice Protocol, a pioneering computer network protocol for transporting human speech over packetized communications networks, first implemented in December 1973 by Internet researcher Danny Cohen of the Information Sciences Institut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IEEE 802
IEEE 802 is a family of Institute of Electrical and Electronics Engineers (IEEE) standards for local area networks (LAN), personal area network (PAN), and metropolitan area networks (MAN). The IEEE 802 LAN/MAN Standards Committee (LMSC) maintains these standards. The IEEE 802 family of standards has had twenty-four members, numbered 802.1 through 802.24, with a working group of the LMSC devoted to each. However, not all of these working groups are currently active. The IEEE 802 standards are restricted to computer networks carrying variable-size packets, unlike cell relay networks, for example, in which data is transmitted in short, uniformly sized units called cells. Isochronous signal networks, in which data is transmitted as a steady stream of octets, or groups of octets, at regular time intervals, are also outside the scope of the IEEE 802 standards. The number 802 has no significance: it was simply the next number in the sequence that the IEEE used for standards projects. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Office Of Technology Assessment
The Office of Technology Assessment (OTA) was an office of the United States Congress that operated from 1974 to 1995. OTA's purpose was to provide congressional members and committees with objective and authoritative analysis of the complex scientific and technical issues of the late 20th century, i.e. technology assessment. It was a leader in practicing and encouraging delivery of public services in innovative and inexpensive ways, including early involvement in the distribution of government documents through electronic publishing. Its model was widely copied around the world. The OTA was authorized in 1972 and received its first funding in fiscal year 1974. It was defunded at the end of 1995, following the 1994 mid-term elections which led to Republican control of the Senate and the House. House Republican legislators characterized the OTA as wasteful and hostile to GOP interests. Princeton University hosts The OTA Legacy site, which holds "the complete collection of OTA publi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wide Area Networks
A wide area network (WAN) is a telecommunications network that extends over a large geographic area. Wide area networks are often established with leased telecommunication circuits. Businesses, as well as schools and government entities, use wide area networks to relay data to staff, students, clients, buyers and suppliers from various locations around the world. In essence, this mode of telecommunication allows a business to effectively carry out its daily function regardless of location. The Internet may be considered a WAN. Design options The textbook definition of a WAN is a computer network spanning regions, countries, or even the world. However, in terms of the application of communication protocols and concepts, it may be best to view WANs as computer networking technologies used to transmit data over long distances, and between different networks. This distinction stems from the fact that common local area network (LAN) technologies operating at lower layers of the O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
