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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 the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nortel DMS10
Nortel Networks Corporation (Nortel), formerly Northern Telecom Limited, was a Canadian multinational telecommunications and data networking equipment manufacturer headquartered in Ottawa, Ontario, Canada. It was founded in Montreal, Quebec, in 1895 as the Northern Electric and Manufacturing Company. Until an antitrust settlement in 1949, Northern Electric was owned principally by Bell Canada and the Western Electric Company of the Bell System, producing large volumes of telecommunication 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 of its corporate stock price. The bankruptcy case was the largest in Canadian history and left pensioners, shareholders and former employees with enormous losses. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AT&T Corporation
AT&T Corporation, originally the American Telephone and Telegraph Company, is the subsidiary of AT&T Inc. that provides voice, video, data, and Internet telecommunications and professional services to businesses, consumers, and government agencies. During the Bell System's long history, AT&T was at times the world's largest telephone company, the world's largest cable television operator, and a regulated monopoly. At its peak in the 1950s and 1960s, it employed one million people and its revenue ranged between US$3 billion in 1950 ($ in present-day terms) and $12 billion in 1966 ($ in present-day terms). In 2005, AT&T was purchased by Baby Bell and former subsidiary SBC Communications for more than $16 billion ($ in present-day terms). SBC then changed its name to AT&T Inc. Today, AT&T Corporation continues to exist as the long distance subsidiary of AT&T Inc., and its name occasionally shows up in AT&T press releases. Buildings with AT&T logo * AT&T Huro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Exchange Equipment
A telephone is a telecommunications device that permits 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 cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from el, τῆλε (''tēle'', ''far'') and φωνή (''phōnē'', ''voice''), together meaning ''distant voice''. A common short form of the term is ''phone'', which came into use early in the telephone's history. 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 micr ... [...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 dev ... [...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] |
Competitive Local Exchange Carrier
A competitive local exchange carrier (CLEC), in the United States and Canada, is a telecommunications provider company (sometimes called a " carrier") competing with other, already established carriers, generally the incumbent local exchange carrier (ILEC). Background Local exchange carriers (LECs) are divided into incumbent (ILECs) and 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 CAPs (such as Teleport Communications Group (TCG) and Metropolitan Fiber Systems (MFS)) deployed fiber optic systems in the central business districts of th ... [...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 30 January 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 30 October 1891. The first Strowger switch went into operation on 3 November 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-profit ru ... [...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 in Montreal, Quebec, 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 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 flanker brand Virgin Mobile Canada) 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, Telus and Shaw Communications in Western Canada, and Quebecor ( Videotron) and Telus in Quebec. The company serves over 13 million phone lines and is headquartered at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RBOC
The Regional Bell Operating Companies (RBOC) are the result of '' United States v. AT&T'', the U.S. Department of Justice antitrust suit against the former American Telephone & Telegraph Company (later known as AT&T Corp.). On January 8, 1982, AT&T Corp. settled the suit and agreed to divest its local exchange service operating companies. Effective January 1, 1984, AT&T Corp.'s local operations were split into seven independent Regional Bell Operating Companies known as the Baby Bells. RBOCs were originally known as Regional Holding Companies (RHCs). Currently, three companies have the RBOCs as predecessors: AT&T, Verizon, and Lumen Technologies. Some other companies are holding onto smaller segments of the companies. Baby Bells A baby bell is local telephone company in the United States that was in existence at the time of the breakup of AT&T into the resulting Regional Bell Operating Companies (RBOCs), also known as the "Baby Bells." Sometimes also referred to as an "ILE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cable Telephony
Cable telephony is a form of digital telephony over cable TV networks. A telephone interface installed at the customer's premises converts 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 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 a single bill for combined television, internet and telephone services. Richard Grigonis (ed) ''Cable Telephony'' in ''Computer Telephony Encyclopedia'', Focal Press, 2000 pp.68-69 Emergency calls The biggest obstacle to cable telephone service is the need for nearly 100% reliable service for emergency calls. PacketCable, one of the emerging standards being developed for digital cable telephony, seems to be the most promising and able to work with the quality of service demands of traditiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SP1 (telecommunications)
SP-1 (Stored Program 1) was the name of a computerized telephone exchange (a so-called switching office) manufactured by Northern Electric (later Northern Telecom and now Nortel Networks beginning in 1972) in Canada. It was introduced in 1971 (as stated in a Northern Telecom print ad that is included (page 55) in a history of Nortel, written by Peter C. Newman who was commissioned by Nortel to write it. Copyright is 1995. No ISBN.) As indicated by the name "Stored Program", the SP-1 introduced computer control to the telephone switching market. (AT&T's #1ESS preceded the SP-1 by several years.) A central computer controlled the operation of the switch. Switch behavior was determined by the operation of a computer program. With its use of computer hardware and software control, the SP-1 marked an evolutionary step in telephony design. It was an intermediate form between the previous generation of electromechanical systems and the next generation of fully digital systems. Like th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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