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Global Network
A global network is any communication network that spans the entire Earth. The term, as used in this article, refers in a more restricted way to ''bidirectional'' communication networks based on technology. Early networks such as international mail and unidirectional communication networks, such as radio and television, are described elsewhere. The first global network was established using electrical telegraphy and global span was achieved in 1899. The telephony network was the second to achieve global status, in the 1950s. More recently, interconnected IP networks (principally the Internet, with estimated 2.5 billion users worldwide in 2014), and the GSM mobile communication network (with over 6 billion worldwide users in 2014) form the largest global networks of all. Setting up global networks requires immensely costly and lengthy efforts lasting for decades. Elaborate interconnections, switching and routing devices, laying out physical carriers of information, such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World Map Of Submarine Cables
The world is the totality of entities, the whole of reality, or everything that Existence, exists. The nature of the world has been conceptualized differently in different fields. Some conceptions see the world as unique, while others talk of a "plurality of worlds". Some treat the world as #Monism and pluralism, one simple object, while others analyze the world as a complex made up of parts. In #Scientific cosmology, scientific cosmology, the world or universe is commonly defined as "the totality of all space and time; all that is, has been, and will be". #Theories of modality, Theories of modality talk of possible worlds as complete and consistent ways how things could have been. #Phenomenology, Phenomenology, starting from the horizon of co-given objects present in the periphery of every experience, defines the world as the biggest horizon, or the "horizon of all horizons". In #Philosophy of mind, philosophy of mind, the world is contrasted with the mind as that which is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communication Protocol
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity. The protocol defines the rules, syntax, semantics (computer science), semantics, and synchronization of communication and possible Error detection and correction, error recovery methods. Protocols may be implemented by Computer hardware, 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 predetermined for that particular situation. The specified behavior is typically independent of how it is to be Implementation, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Internet Access
Satellite Internet access is Internet access provided through communication satellites; if it can sustain high-speed Internet, high speeds, it is termed satellite broadband. Modern consumer grade satellite Internet service is typically provided to individual users through geostationary satellites that can offer relatively high data speeds, with newer satellites using the to achieve downstream data speeds up to 506 Data-rate units#Megabit per second, Mbit/s. In addition, new satellite internet constellations are being developed in Low Earth orbit, low-earth orbit to enable Network delay, low-latency internet access from space. History Following the launch of the first satellite, Sputnik 1, by the Soviet Union in October 1957, the US successfully launched the Explorer 1 satellite in 1958. The first commercial communications satellite was Telstar, Telstar 1, built by Bell Labs and launched in July 1962. The idea of a geosynchronous satellite—one that could orbit the Earth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VSAT
A very-small-aperture terminal (VSAT) is a two-way satellite ground station with a satellite dish, dish antenna that is smaller than 3.8 meters. The majority of VSAT antennas range from 75 cm to 1.2 m. Bit rates, in most cases, range from 4 kbit/s to 16 Mbit/s. VSATs access satellites in geosynchronous orbit or geostationary orbit to relay data from small remote Earth stations (terminals) to other terminals (in mesh networking, mesh Network topology, topology) or master Earth station "hubs" (in star topology). VSATs are used to transmit narrowband data (e.g., point-of-sale transactions using credit cards, polling or RFID data, or SCADA), or broadband data (for the provision of satellite Internet access to remote locations, VoIP or video). VSATs are also used for transportable, on-the-move (utilising phased array antennas) or mobile ocean, maritime communications. History The concept of the geostationary orbit was originated by Russian theorist Konstantin Tsiolkovs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesh Network
A mesh network is a local area network topology in which the infrastructure nodes (i.e. bridges, switches, and other infrastructure devices) connect directly, dynamically and non-hierarchically to as many other nodes as possible and cooperate with one another to efficiently route data to and from clients. This lack of dependency on one node allows for every node to participate in the relay of information. Mesh networks dynamically self-organize and self-configure, which can reduce installation overhead. The ability to self-configure enables dynamic distribution of workloads, particularly in the event a few nodes should fail. This in turn contributes to fault-tolerance and reduced maintenance costs. Mesh topology may be contrasted with conventional star/tree local network topologies in which the bridges/switches are directly linked to only a small subset of other bridges/switches, and the links between these infrastructure neighbours are hierarchical. While star-and-tree topologi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbcomm
ORBCOMM is an American company that offers industrial IoT solutions designed to track, monitor, and control fixed and mobile assets in markets including transportation, heavy equipment, maritime, oil and gas, utilities and government. The company provides hardware devices, modems, web applications, and data services delivered over multiple satellites and cellular networks. As of June 30, 2021, ORBCOMM has more than 2.3 million billable subscriber communicators, serving original equipment manufacturers (OEMs) such as Caterpillar Inc., Doosan Infracore America, Hitachi Construction Machinery Co., Ltd., John Deere, Komatsu Limited, and Volvo Construction Equipment, as well as other customers such as J. B. Hunt, C&S Wholesale Grocers, Canadian National Railways, C.R. England, Hub Group, KLLM Transport Services, Marten Transport, Swift Transportation, Target, Tropicana, Tyson Foods, Walmart and Werner Enterprises. ORBCOMM owns and operates a global network of 31 low Earth o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Globalstar
Globalstar, Inc. is an American telecommunications company that operates a satellite constellation in low Earth orbit (LEO) for satellite phone, low-speed data transmission and earth observation. The Globalstar second-generation constellation consists of 25 satellites. History The Globalstar project was launched in 1991 as a joint venture of Loral Corporation and Qualcomm. On March 24, 1994, the two sponsors announced the formation of Globalstar LP, a limited partnership established in the U.S., with financial participation from eight other companies, including Alcatel, AirTouch, Deutsche Aerospace, Hyundai, and Vodafone. At that time, the company predicted the system would launch in 1998, based on an investment of $1.8 billion. Globalstar said in March 1994 that it expected to charge $0.65 per minute for cellular service, compared to $3 per minute from Iridium. By then it had a worldwide license from the World Administrative Radio Conference. Globalstar received its US spect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridium Satellite Constellation
The Iridium satellite constellation provides L band voice and data information Pass (spaceflight), coverage to satellite phones, satellite messenger communication devices and integrated transceivers. Iridium Communications owns and operates the Satellite constellation, constellation, additionally selling equipment and access to its services. It was conceived by Bary Bertiger, Raymond J. Leopold and Ken Peterson in late 1987 (in 1988 protected by patents Motorola filed in their names) and then developed by Motorola on a fixed-price contract from July 29, 1993, to November 1, 1998, when the system became operational and commercially available. The constellation consists of 66 active satellites in orbit, required for global coverage, and additional spare satellites to serve in case of failure. Satellites are placed in low Earth orbit at a height of approximately and Orbital inclination, inclination of 86.4°. The nearly polar orbit and communication between satellites via Ka band I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Satellite Constellation
A satellite constellation is a group of artificial satellites working together as a system. Unlike a single satellite, a constellation can provide permanent global or near-global pass (spaceflight), coverage, such that at any time everywhere on Earth at least one satellite is visible. Satellites are typically placed in sets of complementary orbital plane (astronomy), orbital planes and connect to globally distributed ground stations. They may also use Inter-satellite service, inter-satellite communication. Other satellite groups Satellite constellations should not be confused with: * ''satellite clusters'', which are groups of satellites moving very close together in almost identical orbits (see satellite formation flying); * '':Satellite series, satellite series'' or ''satellite programs'' (such as Landsat program, Landsat), which are generations of satellites launched in succession; * ''satellite fleets'', which are groups of satellites from the same manufacturer or operator tha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low Earth Orbit
A low Earth orbit (LEO) is an geocentric orbit, orbit around Earth with a orbital period, period of 128 minutes or less (making at least 11.25 orbits per day) and an orbital eccentricity, eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, peaking in number at an altitude around , while the farthest in LEO, before medium Earth orbit (MEO), have an altitude of 2,000 km, about one-third of the Earth radius, radius of Earth and near the beginning of the Van Allen radiation belt#Inner belt, inner Van Allen radiation belt. The term ''LEO region'' is used for the area of space below an altitude of (about one-third of Earth's radius). Objects in orbits that pass through this zone, even if they have an apogee further out or are sub-orbital spaceflight, sub-orbital, are carefully tracked since they present a collision risk to the many LEO satellites. No human spaceflights other than the lunar missions of the Apollo program (1968-1972) have gone beyond L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Communication Satellite
A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. Communications satellites are used for television, telephone, radio, internet, and military applications. Many communications satellites are in geostationary orbit above the equator, so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit, where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The radio waves used for telecommunications links travel by line of sight and so are obstructed by the curve of the Earth. The purpose of communications satellites is to re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Issues
A global issue is a matter of Social issue#Types of social issues, public concern worldwide. This list of global issues presents problems or phenomena affecting people around the world, including but not limited to widespread social issues, economic issues, and environmental issues. Organizations that maintain or have published an official list of global issues include the United Nations, and the World Economic Forum. Global catastrophic risks Not all of these risks are independent, because the majority, if not all of them are a result of human activity. * Biodiversity loss * Climate change * Existential risk from artificial general intelligence, Destructive artificial intelligence * Environmental disaster * Nuclear holocaust * Pandemic * Biotechnology risk * Gray goo, Molecular nanotechnology * Societal collapse United Nations list The United Nations, UN has listed issues that it deems to be the most pressing : As part of the 2030 Agenda for Sustainable Development, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
