|
Wireless Local Loop
Wireless local loop (WLL), is the use of a wireless communications link as the " last mile / first mile" connection for delivering plain old telephone service (POTS) or Internet access (marketed under the term "broadband") to telecommunications customers. Various types of WLL systems and technologies exist. Other terms for this type of access include broadband wireless access (BWA), radio in the loop (RITL), fixed-radio access (FRA), fixed wireless access (FWA) and metro wireless (MW). Definition of fixed wireless service Fixed wireless terminal (FWT) units differ from conventional mobile terminal units operating within cellular networks such as GSM in that a fixed wireless terminal or desk phone will be limited to an almost permanent location with almost no roaming abilities. WLL and FWT are generic terms for radio-based telecommunications technologies and the respective devices, which can be implemented using a number of different wireless and radio technologies. Wireless ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Last Mile (telecommunications)
The last mile or last kilometer is a phrase widely used in the telecommunications, cable television and internet industries to refer to the final leg of the telecommunications networks that deliver telecommunication services to retail end-users (customers). More specifically, the ''last mile'' describes the portion of the telecommunications network chain that physically reaches the end-user's premises. Examples are the copper wire subscriber lines connecting landline telephones to the local telephone exchange; coaxial cable service drops carrying cable television signals from utility poles to subscribers' homes, and cell towers linking local cell phones to the cellular network. The word "mile" is used metaphorically; the length of the last mile link may be more or less than a mile. Because the last mile of a network to the user is conversely the first mile from the user's premises to the outside world when the user is sending data, the term first mile is also alternatively used. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Web
The mobile web refers to mobile browser-based World Wide Web services accessed from handheld mobile devices, such as smartphones or feature phones, through a mobile or other wireless network. History and development Traditionally, the World Wide Web has been accessed via fixed-line services on laptops and desktop computers. However, the web is now more accessible by portable and wireless devices. Early 2010 ITU (International Telecommunication Union) report said that with current growth rates, web access by people on the go via laptops and smart mobile devices was likely to exceed web access from desktop computers within the following five years. In January 2014, mobile internet use exceeded desktop use in the United States. The shift to mobile Web access has accelerated since 2007 with the rise of larger multitouch smartphones, and since 2010 with the rise of multitouch tablet computers. Both platforms provide better Internet access, screens, and mobile browsers, or applica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Mobile Phone System
Advanced Mobile Phone System (AMPS) was an analog mobile phone system standard originally developed by Bell Labs and later modified in a cooperative effort between Bell Labs and Motorola. It was officially introduced in the Americas on October 13, 1983,Private Line and was deployed in many other countries too, including Israel in 1986, Australia in 1987, Singapore in 1988, and Pakistan in 1990. It was the primary analog mobile phone system in North America (and other locales) through the 1980s and into the 2000s. As of February 18, 2008, carriers in the United States were no longer required to support AMPS and companies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Enhanced Cordless Telecommunications
Digital enhanced cordless telecommunications (Digital European cordless telecommunications), usually known by the acronym DECT, is a standard primarily used for creating cordless telephone systems. It originated in Europe, where it is the common standard, replacing earlier cordless phone standards, such as 900 MHz CT1 and CT2. Beyond Europe, it has been adopted by Australia and most countries in Asia and South America. North American adoption was delayed by United States radio-frequency regulations. This forced development of a variation of DECT called DECT 6.0, using a slightly different frequency range, which makes these units incompatible with systems intended for use in other areas, even from the same manufacturer. DECT has almost completely replaced other standards in most countries where it is used, with the exception of North America. DECT was originally intended for fast roaming between networked base stations, and the first DECT product was Net3 wireless LAN ... [...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 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). 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. 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 its radio technologies. It can be also used as a channel or m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time-division Multiple Access
Time-division multiple access (TDMA) is a channel access method for shared-medium networks. It allows several users to share the same frequency channel by dividing the signal into different time slots. The users transmit in rapid succession, one after the other, each using its own time slot. This allows multiple stations to share the same transmission medium (e.g. radio frequency channel) while using only a part of its channel capacity. Dynamic TDMA is a TDMA variant that dynamically reserves a variable number of time slots in each frame to variable bit-rate data streams, based on the traffic demand of each data stream. TDMA is used in the digital 2G cellular systems such as Global System for Mobile Communications (GSM), IS-136, Personal Digital Cellular (PDC) and iDEN, and in the Digital Enhanced Cordless Telecommunications (DECT) standard for portable phones. TDMA was first used in satellite communication systems by Western Union in its Westar 3 communications satellite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ad Hoc Networking
An ad hoc network refers to technologies that allow network communications on an ad hoc basis. Associated technologies include: *Wireless ad hoc network *Mobile ad hoc network *Vehicular ad hoc network **Intelligent vehicular ad hoc network * Protocols associated with ad hoc networking **Ad hoc On-Demand Distance Vector Routing **Ad Hoc Configuration Protocol *Smart phone ad hoc network *Ad hoc wireless distribution service Ad hoc Wireless Distribution Service (AWDS) is a layer 2 routing protocol to connect mobile ad hoc networks, sometimes called wireless mesh networks. It is based on a link-state routing protocol, similar to OLSR. Principle of operation AWDS use ... References Computer networking {{networking-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesh Networking
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] |
Deutsche Telekom
Deutsche Telekom AG (; short form often just Telekom, DTAG or DT; stylised as ·T·) is a German telecommunications company that is headquartered in Bonn and is the largest telecommunications provider in Europe by revenue. Deutsche Telekom was formed in 1995 when Deutsche Bundespost (at that time a monopoly under state ownership) was privatized. Since then, Deutsche Telekom has featured among Fortune 500 companies, with its latest ranking at number 62 (in 2022). The company operates several subsidiaries worldwide, including the mobile communications brand T-Mobile. As of April 2020, the German government holds a 14.5% stake in company stock directly, and another 17.4% through the government bank KfW. The company is a component of the EURO STOXX 50 stock market index. History The Deutsche Bundespost was the federal German government postal administration created in 1947 as a successor to the Reichspost. It was also the major telephone company in West Germany. On 1 July 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etheric Networks
Etheric Networks is an Internet Service Provider based in San Mateo, California serving the San Francisco Bay Area. It specializes in high-speed Internet access using wireless technologies. Fixed wireless towers using ISM and U-NII band transmissions connect end users to its fiber optic backbone. History In March 2003, Etheric Networks launches ISP service via its first generation broadband fixed wireless local loop WLL access network, via the Qwest co-location center in Sunnyvale and Black Mountain, a communication tower complex at 2,800 feet above sea level, overlooking Silicon Valley and the Peninsula. References External links * {{Official website SVBJ on Etheric Silicon Valley Business Journal American City Business Journals, Inc. (ACBJ) is an American newspaper publisher based in Charlotte, North Carolina. ACBJ publishes The Business Journals, which contains local business news for 44 markets in the United States, Hemmings Motor News ... Companies based in Redwoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hidden Node Problem
In wireless networking, the hidden node problem or hidden terminal problem occurs when a node can communicate with a wireless access point (AP), but cannot directly communicate with other nodes that are communicating with that AP. This leads to difficulties in medium access control sublayer since multiple nodes can send data packets to the AP simultaneously, which creates interference at the AP resulting in no packet getting through. Although some loss of packets is normal in wireless networking, and the higher layers will resend them, if one of the nodes is transferring a lot of large packets over a long period, the other node may get very little goodput. Practical protocol solutions exist to the hidden node problem. For example, Request To Send/Clear To Send (RTS/CTS) mechanisms where nodes send short packets to request permission of the access point to send longer data packets. Because responses from the AP are seen by all the nodes, the nodes can synchronize their transmissi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
