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Digital Multiplex System
Digital Multiplex System (DMS) is the name shared among several different telephony product lines from Nortel Networks for wireline and wireless operators. Among them are the DMS-1 (originally named the DMS-256) Rural/Urban digital loop carrier, the DMS-10 telephone switch, the DMS SuperNode family of telephone switches ( DMS-100, DMS-200, DMS-250, DMS-300, DMS-500, DMS-GSP, DMS-MSC, DMS-MTX), and the S/DMS optical transmission system. Exploratory development on the technology began at Northern Telecom's Bell Northern Research Labs in Ottawa, Ontario in 1971. The first Class 5 switch, the DMS-10, began service on 21 October 1977 in Fort White, Florida and the first toll switch (Class 4), the DMS-200, entered service in 1979 in Ottawa. The DMS-10 was the first commercially successful Class 5 digital switch in the North American market and had a profound impact on the industry. Of the numerous digital switching products introduced in the North American telephone market in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nortel DMS10
Nortel Networks Corporation (Nortel), formerly Northern Telecom Limited, was a Canadian Multinational corporation, multinational telecommunications and data networking equipment manufacturer headquartered in Ottawa, Ontario. It was founded in Montreal, Quebec in 1895 as the Northern Electric and Manufacturing Company, or simply Northern Electric. Until an antitrust settlement in 1949, Northern Electric was owned mostly by Bell Canada and the Western Electric, Western Electric Company of the Bell System, producing large volumes of telecommunications equipment based on licensed Western Electric designs. At its height, Nortel accounted for more than a third of the total valuation of all companies listed on the Toronto Stock Exchange (TSX), employing 94,500 people worldwide. In 2009, Nortel filed for bankruptcy protection in Canada and the United States, triggering a 79% decline in its corporate stock price. The bankruptcy case was the List of corporate collapses and scandals, larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Exchange
A telephone exchange, telephone switch, or central office is a central component of a telecommunications system in the public switched telephone network (PSTN) or in large enterprises. It facilitates the establishment of communication circuits, enabling telephone calls between subscribers. The term "central office" can also refer to a central location for fiber optic equipment for a fiber internet provider. In historical perspective, telecommunication terminology has evolved with time. The term ''telephone exchange'' is often used synonymously with ''central office'', a Bell System term. A central office is defined as the telephone switch controlling connections for one or more central office prefixes. However, it also often denotes the building used to house the inside plant equipment for multiple telephone exchange areas. In North America, the term ''wire center'' may be used to denote a central office location, indicating a facility that provides a telephone with a dial tone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Exchange Equipment
A telephone, colloquially referred to as a phone, is a telecommunications device that enables two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via Electrical cable, cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from and (, ''voice''), together meaning ''distant voice''. In 1876, Alexander Graham Bell was the first to be granted a United States patent for a device that produced clearly intelligible replication of the human voice at a second device. This instrument was further developed by many others, and became rapidly indispensable in business, government, and in households. The essential elements of a telephone are a microphone (''transmitter'') to speak into and an earphone (''receiver'') which reproduces the voice a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiplexing
In telecommunications and computer networking, multiplexing (sometimes contracted to muxing) is a method by which multiple analog or digital signals are combined into one signal over a shared medium. The aim is to share a scarce resource—a physical transmission medium. For example, in telecommunications, several telephone calls may be carried using one wire. Multiplexing originated in telegraphy in the 1870s, and is now widely applied in communications. In telephony, George Owen Squier is credited with the development of telephone carrier multiplexing in 1910. The multiplexed signal is transmitted over a communication channel such as a cable. The multiplexing divides the capacity of the communication channel into several logical channels, one for each message signal or data stream to be transferred. A reverse process, known as demultiplexing, extracts the original channels on the receiver end. A device that performs the multiplexing is called a multiplexer (MUX), and a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Telephone Switches
This list of telephone switches is a compilation of telephone switches used in the public switched telephone network (PSTN) or in large enterprises. American Digital Switching * Centura 2000 Alcatel This lists Alcatel switches before the merger with Lucent Technologies. * 1000 E10 / S12 (during the 1990s the E10 and S12 systems were converted into a single product line) * E10 versions: ** E10A (E10N3)- Original switch introduced in 1972 one of the earliest deployments of TDM switching in the world. ** E10B (E10N1)- Major revision in the 1980s which eventually saw ISDN capabilities. Common in France, Ireland, China, India and elsewhere. ** E10B3 - major revision in the 1990s. Common in France & Ireland ** OCB-283 - Another name for more modern versions of E10B and often the name used in India to distinguish it from older versions. ** E10-MT formerly Thomson MT-25 found mostly in France, and MT20 too. ** E10-Five E10B adapted for the North American environment as a class-5 switch. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connections Museum
The Connections Museum (formerly the Herbert H. Warrick Jr. Museum of Communications, originally the Vintage Telephone Equipment Museum) is located in Centurylink's Duwamish Central Office at East Marginal Way S. and Corson Avenue S. in Seattle's Georgetown neighborhood. It "reveals the history of the telephone and the equipment that makes it all work." The museum was originally sponsored by the Washington Telephone Pioneers, and is now a part of the Telecommunications History Group, based in Denver. It features vintage equipment from AT&T, Western Electric, Pacific Northwest Bell, USWest, and other organizations. History The museum was founded by Don Ostrand and Herb Warrick, both employees of Pacific Northwest Bell. As a result of the Modification of Final Judgement in 1984, the AT&T monopoly was broken up, and an organizational mandate required Pacific Northwest Bell to modernize their aging telephone switching equipment. Realizing that this was perhaps the last oppor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Competitive Local Exchange Carrier
A competitive local exchange carrier (CLEC) is a North American telecommunications provider classification that emerged based on the competition model of the Telecommunications Act of 1996 in the United States. The act required the previously established incumbent local exchange carrier (ILEC) in each local market to provide infrastructure hosting and services to CLECs to enable competition with the ILEC. Background Local exchange carriers (LECs) are characterized as incumbent (ILECs) or competitive (CLECs). The ILECs are usually the original, monopoly LEC in a given area, and receive different regulatory treatment from the newer CLECs. A data local exchange carrier (DLEC) is a CLEC specializing in DSL services by leasing lines from the ILEC and reselling them to Internet service providers (ISPs). History CLECs evolved from the competitive access providers (CAPs) that began to offer private line and special access services in competition with the ILECs beginning in 1985. The CA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autovon
The Automatic Voice Network (AUTOVON, military designation 490-L) was a worldwide American military telephone system. The system was built starting in 1963, based on the Army's existing Switch Communications Automated Network (SCAN) system. In June 1966, the Air Defense Command voice network was cut over to the new service. In 1969, AUTOVON switching centers opened in the United Kingdom, and later in other European countries, Asia, the Middle East, and Panama. It was a major part of the Defense Communications System (DCS), providing non-secure switched voice services. The system was replaced in the early 1990s by the Defense Switched Network. Circuits AUTOVON used a combination of its own constructed circuits and other lines operated by AT&T Corporation and smaller independent telephone companies, connected by high-speed switching centers produced by Automatic Electric Company to exchanges located far from other civilian or military targets. In the US the cables were predomi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Independent Telephone Companies
An independent telephone company was a telephone company providing local service in the United States or Canada that was not part of the Bell System organized by American Telephone and Telegraph. Independent telephone companies usually operated in many rural or sparsely populated areas. United States The second fundamental Bell patent for telephones expired on January 30, 1894, which provided an opportunity for independent companies to provide telephone services, although some had been established before that date. The Strowger Automatic Telephone Exchange company had been formed on October 30, 1891. The first Strowger switch went into operation on November 3, 1892, in LaPorte, Indiana, with 75 subscribers and capacity for 99. Independent manufacturing companies were established, such as Stromberg-Carlson in 1894 and Kellogg Switchboard & Supply Company in 1897. By 1903 while the Bell system had 1,278,000 subscribers on 1,514 main exchanges, the independents, excluding non-pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell Canada
Bell Canada (commonly referred to as Bell) is a Canadian telecommunications company headquartered at 1 Carrefour Alexander-Graham-Bell in the borough of Verdun, Quebec, in Canada. It is an ILEC (incumbent local exchange carrier) in the provinces of Ontario and Quebec; as such, it was a founding member of the Stentor Alliance. It is also a Competitive local exchange carrier, CLEC (competitive local exchange carrier) for enterprise customers in the western provinces. Its subsidiary Bell Aliant provides services in the Atlantic provinces. It provides mobile service through its Bell Mobility (including Individual branding, flanker brand Virgin Plus) subsidiary, and television through its Bell Satellite TV (direct broadcast satellite) and Bell Fibe TV (IPTV) subsidiaries. Bell Canada's principal competitors are: Rogers Communications in Ontario and Western Canada, Telus Communications in Quebec and Western Canada, Quebecor (Videotron) in Quebec plus other Global Wireless Infrastruct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RBOC
A Regional Bell Operating Company (RBOC) was a corporate entity created as result of the antitrust lawsuit by the United States Department of Justice against the Western Electric Company and American Telephone and Telegraph Company (AT&T) in 1949 and a suit in 1974 against AT&T ('' United States v. AT&T''). The suits were settled in the Modification of Final Judgment in August 1982. AT&T agreed to divest its local exchange service operating companies, effective January 1, 1984. The group of local operating companies were split into seven independent Regional Bell Operating Companies, which became known as the Baby Bells. Three companies still exist that have an RBOC as a predecessor: AT&T, Verizon, and Lumen Technologies (formerly CenturyTel and CenturyLink). Some other companies are holding onto smaller segments of the companies. Baby Bells A "Baby Bell" is a local telephone company in the United States that was in existence at the time of the breakup of AT&T into the resu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Telephony
Cable telephony is a form of digital telephony over Hybrid fiber-coaxial, cable TV type networks. A telephone interface installed at the customer's premises converting analog signals from the customer's in-home wiring to a digital signal, which is then sent over the cable connection to the company's Cable television headend switching center. The signal is then sent on to the public switched telephone network (PSTN). Cable telephone provides another revenue stream for cable television system operators and gives the consumer the convenience of combing several services on a single bill - such as paid television, internet and telephone services. Richard Grigonis (ed) ''Cable Telephony'' in ''Computer Telephony Encyclopedia'', Focal Press, 2000 pp.68-69 At times in the industry this is referred to as "Triple play (telecommunications), triple play". Emergency calls The biggest obstacle to cable telephone service is the need for nearly 100% reliable service for emergency calls. Packe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
