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Mobile WiMAX
Worldwide Interoperability for Microwave Access (WiMAX) is a family of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) options. The WiMAX Forum was formed in June 2001 to promote conformity and interoperability, including the definition of system profiles for commercial vendors. The forum describes WiMAX as "a standards-based technology enabling the delivery of Last mile (telecommunications), last mile wireless broadband access as an alternative to Cable modem, cable and Digital subscriber line, DSL". WiMAX was initially designed to provide 30 to 40 megabit-per-second data rates, with the 2011 update providing up to 1 Gbit/s for fixed stations. IEEE 802.16m or Wireless MAN-Advanced was a candidate for 4G, in competition with the LTE Advanced standard. WiMAX release 2.1, popularly branded as WiMAX 2+, is a backwards-compatible transition from previous WiMAX generations. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long-range Wi-Fi
Long-range Wi-Fi is used for low-cost, unregulated point-to-point computer network connections, as an alternative to other fixed wireless, cellular networks or satellite Internet access. Wi-Fi networks have a range that's limited by the frequency, transmission power, antenna type, the location they're used in, and the environment. A typical wireless router in an indoor point-to-multipoint arrangement using 802.11n and a stock antenna might have a range of or less. Outdoor point-to-point arrangements, through use of directional antennas, can be extended with many kilometers between stations. Introduction Since the development of the IEEE 802.11 radio standard (marketed under the Wi-Fi brand name), the technology has become markedly less expensive and achieved higher bit rates. Long-range Wi-Fi especially in the 2.4 GHz band (as the shorter-range higher-bit-rate 5.8 GHz bands become popular alternatives to wired LAN connections) have proliferated with specialist devi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microwave Link
Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300 MHz to 300 GHz (1 m - 1 mm wavelength) of the electromagnetic spectrum. Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter, but such systems are expensive and generally used only in specialist roles. Although an experimental microwave telecommunication link across the English Channel was demonstrated in 1931, the development of radar in World War II provided the technology for practical exploitation of microwave communication. During the war, the British Army introduced the Wireless Set No. 10, which used microwave relays to multiplex eight telephone channels over long distances. A link across the En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Wiring
Electrical wiring is an electrical installation of Electrical cable, cabling and associated devices such as switches, distribution boards, sockets, and light fittings in a structure. Wiring is subject to safety standards for design and installation. Allowable wire and electrical cable, cable types and sizes are specified according to the circuit operating voltage and electric current capability, with further restrictions on the environmental conditions, such as ambient temperature range, moisture levels, and exposure to sunlight and chemicals. Associated circuit protection, control, and distribution devices within a building's wiring system are subject to voltage, current, and functional specifications. Wiring safety codes vary by locality, country, or region. The International Electrotechnical Commission (IEC) is attempting to harmonise wiring standards among member countries, but significant variations in design and installation requirements still exist. Wiring methods ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Code-division Multiple Access
Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of channel access method, multiple access, where several transmitters can send information simultaneously over a single communication channel. This allows several users to share a band of frequencies (see bandwidth (signal processing), bandwidth). To permit this without undue interference between the users, CDMA employs spread spectrum technology and a special coding scheme (where each transmitter is assigned a code). CDMA optimizes the use of available bandwidth as it transmits over the entire frequency range and does not limit the user's frequency range. It is used as the access method in many mobile phone standards. cdmaOne, IS-95, also called "cdmaOne", and its 3G evolution CDMA2000, are often simply referred to as "CDMA", but UMTS, the 3G standard used by GSM carriers, also uses "wideband CDMA", or W-CDMA, as well as TD-CDMA and TD-SCDMA, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cellular Phone
A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This radio frequency link connects to the switching systems of a mobile phone operator, providing access to the public switched telephone network (PSTN). Modern mobile telephony relies on a cellular network architecture, which is why mobile phones are often referred to as 'cell phones' in North America. Beyond traditional voice communication, digital mobile phones have evolved to support a wide range of additional services. These include text messaging, multimedia messaging, email, and internet access (via LTE, 5G NR or Wi-Fi), as well as short-range wireless technologies like Bluetooth, infrared, and ultra-wideband (UWB). Mobile phones also support a variety of multimedia capabilities, such as digital photography, video recording, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FTTx
Fiber to the ''x'' (FTTX; also spelled "fibre") or fiber in the loop is a generic term for any broadband network architecture using optical fiber to provide all or part of the local loop used for last mile telecommunications. As fiber optic cables are able to carry much more data than copper cables, especially over long distances, copper telephone networks built in the 20th century are being replaced by fiber. The carrier equipment for FTTx is often housed in a "fiber hut", point of presence or central office. FTTX is a generalization for several configurations of fiber deployment, arranged into two groups: FTTP/FTTH/FTTB (fiber laid all the way to the premises/home/building) and FTTC/N (fiber laid to the cabinet/node, with copper wires completing the connection). Residential areas already served by balanced pair distribution plant call for a trade-off between cost and capacity. The closer the fiber head, the higher the cost of construction and the higher the channel capa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybrid Fibre-coaxial
Hybrid fiber-coaxial (HFC) is a broadband telecommunications network that combines optical fiber and coaxial cable. It has been commonly employed globally by cable television operators since the early 1990s. In a hybrid fiber-coaxial cable system, television channels are sent from the cable system's distribution facility, the headend, to local communities through optical fiber subscriber lines. At the local community, an optical node translates the signal from a light beam to radio frequency (RF), and sends it over coaxial cable lines for distribution to subscriber residences. The fiber optic trunk lines provide enough bandwidth to allow additional bandwidth-intensive services such as cable internet access through DOCSIS. Bandwidth is shared among users of an HFC. Encryption is used to prevent eavesdropping. Customers are grouped into service groups, which are groups of customers that share bandwidth among each other since they use the same RF channels to communicate with t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XDSL
Digital subscriber line (DSL; originally digital subscriber loop) is a family of technologies that are used to transmit digital data over telephone lines. In telecommunications marketing, the term DSL is widely understood to mean asymmetric digital subscriber line (ADSL), the most commonly installed DSL technology, for Internet access. In ADSL, the data throughput in the upstream direction (the direction to the service provider) is lower, hence the designation of ''asymmetric'' service. In symmetric digital subscriber line (SDSL) services, the downstream and upstream data rates are equal. DSL service can be delivered simultaneously with wired telephone service on the same telephone line since DSL uses higher frequency bands for data transmission. On the customer premises, a DSL filter is installed on each telephone to prevent undesirable interaction between DSL and telephone service. The bit rate of consumer ADSL services typically ranges from up to , while the later VDSL+ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HSDPA
High Speed Packet Access (HSPA) is an amalgamation of two mobile protocols—High Speed Downlink Packet Access (HSDPA) and High Speed Uplink Packet Access (HSUPA)—that extends and improves the performance of existing 3G mobile telecommunication networks using the WCDMA protocols. A further-improved 3GPP standard called Evolved High Speed Packet Access (also known as HSPA+) was released late in 2008, with subsequent worldwide adoption beginning in 2010. The newer standard allows bit rates to reach as high as 337 Mbit/s in the downlink and 34 Mbit/s in the uplink; however, these speeds are rarely achieved in practice. Overview The first HSPA specifications supported increased peak data rates of up to 14 Mbit/s in the downlink and 5.76 Mbit/s in the uplink. They also reduced latency and provided up to five times more system capacity in the downlink and up to twice as much system capacity in the uplink compared with original WCDMA protocol. High Speed D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Access
Internet access is a facility or service that provides connectivity for a computer, a computer network, or other network device to the Internet, and for individuals or organizations to access or use applications such as email and the World Wide Web. Internet access is offered for sale by an international hierarchy of Internet service providers (ISPs) using various networking technologies. At the retail level, many organizations, including municipal entities, also provide cost-free access to the general public. Types of connections range from fixed-line cable (such as DSL and fiber optic) to Mobile broadband, mobile (via Cellular network, cellular) and Satellite Internet access, satellite. The availability of Internet access to the general public began with the commercialization of the early Internet in the early 1990s, and has grown with the availability of useful applications, such as the World Wide Web. In 1995, only percent of the world's population had access, with well ove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Business Continuity
Business continuity may be defined as "the capability of an organization to continue the delivery of products or services at pre-defined acceptable levels following a disruptive incident", and business continuity planning (or business continuity and resiliency planning) is the process of creating systems of prevention and recovery to deal with potential threats to a company. In addition to prevention, the goal is to enable ongoing operations before and during execution of disaster recovery. Business continuity is the intended outcome of proper execution of both business continuity planning and disaster recovery. Several business continuity standards have been published by various standards bodies to assist in checklisting ongoing planning tasks. Business continuity requires a top-down approach to identify an organisation's minimum requirements to ensure its viability as an entity. An organization's resistance to failure is "the ability ... to withstand changes in its environmen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
