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G.992.3 Annex J
Annex J is a specification in ITU-T Recommendations G.992.3 and G.992.5 for all digital mode ADSL with improved spectral compatibility with ADSL over ISDN, which means that it is a type of naked DSL which will not disturb existing Annex B ADSL services in the same cable binder. This specification has the same upstream/downstream frequency split of 276 kHz as Annex B, but does not have lower frequency limit of 138 kHz, allowing upstream bandwidth to be increased from 1.8 Mbit/s to 3.5 Mbit/s. This is similar to Annex M, but Annex J can not have POTS on the same line. Deutsche Telekom started deploying Annex J in 2011, Vodafone Vodafone Group Public Limited Company () is a British Multinational company, multinational telecommunications company. Its registered office and global headquarters are in Newbury, Berkshire, England. It predominantly operates Service (economic ... Germany followed suit in April 2015 (marketed as quality improvements). External linksI ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU-T
The International Telecommunication Union Telecommunication Standardization Sector (ITU-T) is one of the three Sectors (branches) of the International Telecommunication Union (ITU). It is responsible for coordinating Standardization, standards for telecommunications and Information Communication Technology, such as X.509 for cybersecurity, Y.3172 and Y.3173 for machine learning, and H.264/MPEG-4 AVC for video compression, between its Member States, Private Sector Members, and Academia Members. The World Telecommunication Standardization Assembly (WTSA), the sector's governing conference, convenes every four years. ITU-T has a permanent Secretariat (administrative office), secretariat called the Telecommunication Standardization Bureau (TSB), which is based at the ITU headquarters in Geneva, Switzerland. The current director of the TSB is Seizo Onoe (of Japan), whose 4-year term commenced on 1 January 2023. Seizo Onoe succeeded Chaesub Lee of South Korea, who was director from 1 J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunications
Telecommunication, often used in its plural form or abbreviated as telecom, is the transmission of information over a distance using electronic means, typically through cables, radio waves, or other communication technologies. These means of transmission may be divided into communication channels for multiplexing, allowing for a single medium to transmit several concurrent Session (computer science), communication sessions. Long-distance technologies invented during the 20th and 21st centuries generally use electric power, and include the electrical telegraph, telegraph, telephone, television, and radio. Early telecommunication networks used metal wires as the medium for transmitting signals. These networks were used for telegraphy and telephony for many decades. In the first decade of the 20th century, a revolution in wireless communication began with breakthroughs including those made in radio communications by Guglielmo Marconi, who won the 1909 Nobel Prize in Physics. Othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADSL2
ITU G.992.3 is an ITU (International Telecommunication Union) standard, also referred to as ADSL2 or G.dmt.bis. It optionally extends the capability of basic ADSL in data rates to 12 Mbit/s downstream and, depending on Annex version, up to 3.5 Mbit/s upstream (with a mandatory capability of ADSL2 transceivers of 8 Mbit/s downstream and 800 kbit/s upstream). ADSL2 uses the same bandwidth as ADSL but achieves higher throughput via improved modulation techniques. Actual speeds may decrease depending on line quality; usually the most significant factor in line quality is the distance from the DSLAM to the customer's equipment. Annex versions ADSL2 has multiple modes for DSL providers to offer services for different needs. Below is a list of available features based on ADSL2 specs from the ITU standards. See also * ADSL * ADSL2+ * List of interface bit rates * Wetting current In electrical and electronics engineering, wetting current is the minimum electric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADSL2+
G.992.5 (also referred to as ADSL2+, G.dmt.bis+, and G.adslplus) is an ITU-T standard for asymmetric digital subscriber line (ADSL) broadband Internet access. The standard has a maximum theoretical downstream sync speed of 24 megabits per second (Mbit/s). Utilizing G.992.5 Annex M upstream sync speeds of 3.3 Mbit/s can be achieved. Technical information ADSL2+ extends the capability of basic ADSL by doubling the number of downstream channels. The data rates can be as high as 24 Mbit/s downstream and up to 1.4 Mbit/s upstream depending on the distance from the DSLAM to the customer's premises. ADSL2+ is capable of doubling the frequency band of typical ADSL connections from 1.1 MHz to 2.2 MHz. This doubles the downstream data rates of the previous ADSL2 standard (which was up to 12 Mbit/s), and like the previous standards will degrade from its peak bitrate after a certain distance. ADSL2+ also allows port bonding. This is where multiple port ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISDN
Integrated Services Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the digitalised circuits of the public switched telephone network. Work on the standard began in 1980 at Bell Labs and was formally standardized in 1988 in the CCITT "Red Book". By the time the standard was released, newer networking systems with much greater speeds were available, and ISDN saw relatively little uptake in the wider market. One estimate suggests ISDN use peaked at a worldwide total of 25 million subscribers at a time when 1.3 billion analog lines were in use. ISDN has largely been replaced with digital subscriber line (DSL) systems of much higher performance. Prior to ISDN, the telephone system consisted of digital links like T1/ E1 on the long-distance lines between telephone company offices and analog signals on copper telephone wires to the customers, the " last mile". At the time, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naked DSL
A naked DSL, also known as standalone or dry loop DSL, is a digital subscriber line (DSL) without a PSTN ( analogue telephony) service — or the associated dial tone. In other words, only a standalone DSL Internet service is provided on the local loop. The original concept of DSL was to use existing telephone lines for high speed data communication, with DSL and telephone services coexisting on the same phone line - but increasingly customers may require ''only'' the Internet service - and see no need for the traditional phone service. Comparison of Regular and Naked DSL (Standalone DSL) In Regular DSL, data transmission is carried on inaudible high frequencies on a standard Plain Old Telephone Service (POTS) telephone line. The original idea was to use existing telephone lines for high speed data communication. DSL and telephone service can coexist on the same phone line and do not interfere with each other. From the Telco's point of view, DSL gives them the ability ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mbit/s
In telecommunications, data transfer rate is the average number of bits (bitrate), characters or symbols (baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are multiples of bits per second (bit/s) and bytes per second (B/s). For example, the data rates of modern residential high-speed Internet connections are commonly expressed in megabits per second (Mbit/s). Standards for unit symbols and prefixes Unit symbol The International System of Quantities, ISQ symbols for the bit and byte are ''bit'' and ''B'', respectively. In the context of data-rate units, one byte consists of 8 bits, and is synonymous with the unit Octet (computing), octet. The abbreviation bps is often used to mean bit/s, so that when a ''1 Mbps'' connection is advertised, it usually means that the maximum achievable bandwidth is 1 Mbit/s (one million bits per second), which is 0.125 MB/s (megabyte per second), or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ITU G
The International Telecommunication Union (ITU)In the other common languages of the ITU: * * is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Union, the first formal and permanent international organization. The organization significantly predates the UN, making it the oldest UN agency. Doreen Bogdan-Martin is the Secretary-General of ITU, the first woman to serve as its head. The ITU was initially aimed at helping connect telegraphic networks between countries, with its mandate consistently broadening with the advent of new communications technologies; it adopted its current name in 1932 to reflect its expanded responsibilities over radio and the telephone. On 15 November 1947, the ITU entered into an agreement with the newly created United Nations to become a specialized agency within the UN system, which formally entered into for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plain Old Telephone Service
Plain old telephone service (POTS), or publicly offered telephone service, is basic Voice band, voice-grade telephone service. Historically, POTS has been delivered by Analog signal, analog signal transmission over copper loops, but the term also describes Backward compatibility, backward-compatible analog connections offered by digital telephone systems. Copper loop POTS was the standard service offering from telephone companies in the United States from 1876 until 1988, when the Integrated Services Digital Network (ISDN) Basic Rate Interface (BRI) was introduced, followed by the development of mobile phone, cellular telephone systems and voice over internet protocol (VoIP). Despite the advent of these technologies, copper loop POTS remains a basic form of residential and small business connection to the telephone network in many parts of the world. The term encapsulates a technology that has been available since the introduction of the public telephone system in the late 19th c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deutsche Telekom
Deutsche Telekom AG (, ; often just Telekom, DTAG or DT; stylised as ·T·) is a partially state-owned German telecommunications company headquartered in Bonn and the largest telecommunications provider in Europe by revenue. It was formed in 1995 when , a state monopoly at the time, was privatized and broken up. Since then, Deutsche Telekom has consistently featured among Fortune (magazine), ''Fortune'' ''Magazine'''s top Fortune Global 500, Global 500 companies by revenue, with its ranking at number 79. In 2023, the company was ranked 41st in the Forbes Global 2000. The company operates several subsidiaries worldwide, including the mobile communications brand T-Mobile (brand), T-Mobile. It is the world's List of telephone operating companies, fifth-largest telecommunications company and biggest in Europe by revenue. , the German government held a direct 14.5% stake in company stock and another 17.4% through the government bank KfW. On 4th June 2024, the German government reduce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vodafone
Vodafone Group Public Limited Company () is a British Multinational company, multinational telecommunications company. Its registered office and global headquarters are in Newbury, Berkshire, England. It predominantly operates Service (economics), services in Asia, Africa, Europe, and Oceania. , Vodafone owns and operates networks in 15 countries, with partner networks in 46 further countries. Its Vodafone Global Enterprise division provides telecommunications and IT services to corporate clients in 150 countries. Vodafone has a primary listing on the London Stock Exchange and is a constituent of the FTSE 100 Index. The company has a secondary listing on the NASDAQ as American depositary receipts (ADRs). Name The name Vodafone comes from ''voice data fone'' (the latter a sensational spelling of "telephone, phone"), chosen by the company to "reflect the provision of voice and data services over mobile phones". History Racal Telecom: 1980 to 1991 In 1980, Ernest Harrison, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ADSL Annex Overview
Asymmetric digital subscriber line (ADSL) is a type of digital subscriber line (DSL) technology, a data communications technology that enables faster data transmission over copper telephone lines than a conventional voiceband modem can provide. ADSL differs from the less common symmetric digital subscriber line (SDSL). In ADSL, bandwidth and bit rate are said to be asymmetric, meaning greater toward the customer premises ( downstream) than the reverse ( upstream). Providers usually market ADSL as an Internet access service primarily for downloading content from the Internet, but not for serving content accessed by others. Overview ADSL works by using spectrum above the band used by voice telephone calls. With a DSL filter, often called ''splitter'', the frequency bands are isolated, permitting a single telephone line to be used for both ADSL service and telephone calls at the same time. ADSL is generally only installed for short distances from the telephone exchange (the last ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
