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Data Access Arrangement
The term data access arrangement (DAA) has the following meanings: #In public switched telephone networks, a single item or group of items at the customer side of the network interface device for data transmission purposes, including all equipment that may affect the characteristics of the interface. #A data circuit-terminating equipment ( DCE) supplied or approved by a common carrier that permits a DCE or data terminal equipment ( DTE) to be attached to the common carrier network. Data access arrangements are an integral part of all modems built for the public telephone network. In view of mixed voice and data access, DAAs are more generally referred to as direct access arrangements. Requirement for DAAs While DAA now describes an integral component of a device that connects to the telephone network, during the 60s and 70s it described a separate device mandated by the Bell System, connected between the telephone line and non-Bell equipment, typically a modem. Following th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fritz!Box Fon WLAN 7270 - IXYS Litelink CPC5621A-3340
Fritz!Box, stylised as FRITZ!Box, is a series of residential gateway devices produced by the German company AVM GmbH. In 2010 it was estimated the series had a market share of 68% of the digital subscriber line (DSL) consumer equipment in Germany. Functionality Typical functionality of a Fritz!Box includes: * a built-in broadband modem: ** a DSL modem (most models) ** a cable modem (6xxx series) ** a 3G or LTE modem (68xx series) ** a fibre broadband modem (54xx series) * a built-in LAN-WAN router, usually with a network switch supporting Fast Ethernet or, in newer models, Gigabit Ethernet * in nearly all models, a wireless access point: ** in the 2.4 GHz radio band, in accordance with IEEE 802.11b (11 Mbit/s), IEEE 802.11g (54 Mbit/s) and IEEE 802.11n (up to 450 Mbit/s) standards ** in many newer models, also in the 5 GHz radio band, supporting the IEEE 802.11a (54 Mbit/s), IEEE 802.11n (54 Mbit/s—450 Mbit/s) and IEEE 802.11ac (up to 1.27& ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public Switched Telephone Network
The public switched telephone network (PSTN) provides infrastructure and services for public telecommunication. The PSTN is the aggregate of the world's circuit-switched telephone networks that are operated by national, regional, or local telephony operators. These consist of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all interconnected by switching centers which allow most telephones to communicate with each other. Originally a network of fixed-line analog telephone systems, the PSTN is now almost entirely digital in its core network and includes mobile and other networks, as well as fixed telephones. The technical operation of the PSTN adheres to the standards created by the ITU-T. These standards allow different networks in different countries to interconnect seamlessly. The E.163 and E.164 standards provide a single global address space for telephone numbers. The com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Interface Device
upTwo simple NIDs, carrying six lines each, on the outside of a building upA German copper phone line termination box called '' Abschlusspunkt LinienTechnik'' (APL, " Demarcation point") In telecommunications, a network interface device (NID; also known by several other names) is a device that serves as the demarcation point between the carrier's local loop and the customer's premises wiring. Outdoor telephone NIDs also provide the subscriber with access to the station wiring and serve as a convenient test point for verification of loop integrity and of the subscriber's inside wiring. Naming Generically, an NID may also be called a network interface unit (NIU), telephone network interface (TNI), system network interface (SNI), or telephone network box. Australia's National Broadband Network uses the term '' network termination device'' or NTD. A smartjack is a type of NID with capabilities beyond simple electrical connection, such as diagnostics. An '' optical network te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Transmission
Data transmission and data reception or, more broadly, data communication or digital communications is the transfer and reception of data in the form of a digital bitstream or a digitized analog signal transmitted over a point-to-point or point-to-multipoint communication channel. Examples of such channels are copper wires, optical fibers, wireless communication using radio spectrum, storage media and computer buses. The data are represented as an electromagnetic signal, such as an electrical voltage, radiowave, microwave, or infrared signal. Analog transmission is a method of conveying voice, data, image, signal or video information using a continuous signal which varies in amplitude, phase, or some other property in proportion to that of a variable. The messages are either represented by a sequence of pulses by means of a line code (''baseband transmission''), or by a limited set of continuously varying waveforms (''passband transmission''), using a digital modulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunication Circuit
A telecommunication circuit is a path in a telecommunications network used to transmit information. Circuits have evolved over time from generally being built on physical connections between individual hardware cables, as in an analog phone switch, to virtual circuits established over packet switching networks. Definitions A telecommunication circuit may be defined as follows: * The complete path between two terminals over which one-way or two-way communications may be provided. * An electronic path between two or more points, capable of providing a single or multiple communication channels. * An electronic closed-loop path among two or more points used for signal transfer. In operational terms, a telecommunication circuit may be capable of transmitting information in only one direction (''simplex'' circuit), or it may be bi-directional (''duplex'' circuit). Bi-directional circuits may support half- duplex operation, when only one end of the channel transmits at any one tim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Circuit-terminating Equipment
A data circuit-terminating equipment (DCE) is a device that sits between the data terminal equipment (DTE) and a data transmission circuit. It is also called data communication(s) equipment and data carrier equipment. Usually, the DTE device is the terminal (or computer), and the DCE is a modem. In a ''data station'', the DCE performs functions such as signal conversion, coding, and line clocking and may be a part of the DTE or intermediate equipment. Interfacing equipment may be required to couple the DTE into a transmission circuit or channel and from a transmission circuit or channel into the DTE. Usage Although the terms are most commonly used with RS-232, several data communication standards define different types of interfaces between a DCE and a DTE. The DCE is a device that communicates with a DTE device in these standards. Standards that use this nomenclature include: * Federal Standard 1037C, MIL-STD-188 * RS-232 * Certain ITU-T standards in the V series (notabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Carrier
A common carrier in common law countries (corresponding to a public carrier in some civil law systems,Encyclopædia Britannica CD 2000 "Civil-law public carrier" from "carriage of goods" usually called simply a ''carrier'') is a person or company that transports goods or people for any person or company and is responsible for any possible loss of the goods during transport.Longman Business English Dictionary A common carrier offers its services to the general public under license or authority provided by a regulatory body, which has usually been granted "ministerial authority" by the legislation that created it. The regulatory body may create, interpret, and enforce its regulations upon the common carrier (subject to judicial review) with independence and finality as long as it acts within the bounds of the enabling legislation. A common carrier (also called a ''public carrier'' in British English) is distinguished from a contract carrier, which is a carrier that transports go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminal Equipment
In telecommunication, the term terminal equipment has the following meanings: * Communications equipment at either end of a communications link, used to permit the stations involved to accomplish the mission for which the link was established. * In radio-relay systems, equipment used at points where data are inserted or derived, as distinct from equipment used only to relay a reconstituted signal. * Telephone and telegraph Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas ... switchboards and other centrally located equipment at which communications circuits are terminated. See also * Customer-premises equipment * Data terminal equipment, an end instrument that converts user information into signals for transmission or reconverts the received signals into user information Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Terminal Equipment
Data terminal equipment (DTE) is an end instrument that converts user information into signals or reconverts received signals. These can also be called tail circuits. A DTE device communicates with the data circuit-terminating equipment (DCE). The DTE/DCE classification was introduced by IBM. A DTE is the functional unit of a data station that serves as a data source or a data sink and provides for the data communication control function to be performed in accordance with the link protocol. Usually, the DTE device is the terminal (or a computer emulating a terminal), and the DCE is a modem or another carrier-owned device. The data terminal equipment may be a single piece of equipment or an interconnected subsystem of multiple pieces of equipment that perform all the required functions necessary to permit users to communicate. A user interacts with the DTE (e.g. through a human-machine interface), or the DTE may be the user. Connections Two different types of devices are as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Access
Data access is a generic term referring to a process which has both an IT-specific meaning and other connotations involving access rights in a broader legal and/or political sense. In the former it typically refers to software and activities related to storing, retrieving, or acting on data housed in a database or other repository. Details Two fundamental types of data access exist: # sequential access (as in magnetic tape, for example) # random access (as in indexed media) Data access crucially involves authorization to access different data repositories. Data access can help distinguish the abilities of administrators and users. For example, administrators may have the ability to remove, edit and add data, while general users may not even have "read" rights if they lack access to particular information. Historically, each repository (including each different database, file system, etc.), might require the use of different methods and languages, and many of these repositories ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Modem
A modulator-demodulator or modem is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. A modem transmits data by Modulation#Digital modulation methods, modulating one or more carrier wave signals to encode digital information, while the receiver Demodulation, demodulates the signal to recreate the original digital information. The goal is to produce a Signal (electronics), signal that can be transmitted easily and decoded reliably. Modems can be used with almost any means of transmitting analog signals, from light-emitting diodes to radio. Early modems were devices that used audible sounds suitable for transmission over traditional telephone systems and leased lines. These generally operated at 110 or 300 bits per second (bit/s), and the connection between devices was normally manual, using an attached telephone handset. By the 1970s, higher speeds of 1,200 and 2,400 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carterfone
The Carterfone is a device invented by Thomas Carter. It manually connects a two-way radio system to the telephone system, allowing someone on the radio to talk to someone on the phone. This makes it a direct predecessor to today's autopatch. Description The device was acoustically, but not electrically, connected to the public switched telephone network. It was electrically connected to the base station of the mobile radio system, and got its power from the base station. All electrical parts were encased in bakelite, an early plastic. When someone on a two-way radio wished to speak to someone on phone, or "landline" (e.g., "Central dispatch, patch me through to McGarrett"), the station operator at the base would dial the telephone number. When callers on the radio and on the telephone were both in contact with the base station operator, the handset of the operator's telephone was placed on a cradle built into the Carterfone device. A voice-operated switch in the Carte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
