All > Technology > Telecommunications
Abbreviation for tera (1012). See International System of Units.
- Browse Related Terms: ALU, ARU, bits per inch (b/in), MAU, PDU, SI, T, TCU, VDU, vu
Also listed in:
All > Technology > Telecommunications
- The generic designator for any of several digitally multiplexed telecommunications carrier systems.
Note 1: The designators for T-carrier in the North American digital hierarchy correspond to the designators for the digital signal (DS) level hierarchy. See the associated table below.
Note 2: T-carrier systems were originally designed to transmit digitized voice signals. Current applications also include digital data transmission.
Note 3: If an "F" precedes the "T", a fiber optic cable system is indicated at the same rates.
Note 4: The table below lists the designators and rates for current T-Carrier systems.
Note 5: The North American and Japanese hierarchies are based on multiplexing 24 voice-frequency channels and multiples thereof, whereas the European hierarchy is based on multiplexing 30 voice-frequency channels and multiples thereof. See table below.T-Carrier Systems North American Japanese European (CEPT) Level zero (Channel data rate) 64 kb/s (DS0) 64 kb/s 64 kb/s First level 1.544 Mb/s (DS1) (24 user channels) 1.544Mb/s (24 user channels) 2.048 Mb/s (30 user channels) (Intermediate level, North American Hierarchy only) 3.152 Mb/s (DS1C) (48 Ch.) - - Second level 6.312 Mb/s (DS2) (96 Ch.) 6.312 Mb/s (96 Ch.), or 7.786 Mb/s (120 Ch.) 8.448 Mb/s (120 Ch.) Third level 44.736 Mb/s (DS3) (672 Ch.) 32.064 Mb/s (480 Ch.) 34.368 Mb/s (480 Ch.) Fourth level 274.176 Mb/s (DS4) (4032 Ch.) 97.728 Mb/s (1440 Ch.) 139.268 Mb/s (1920 Ch.) Fifth level 400.352 Mb/s (5760 Ch.) 565.148 Mb/s (7680 Ch.) 565.148 Mb/s (7680 Ch.) Note 1: The DS designations are used in connection with the North American hierarchy only.
Note 2: There are other data rates in use, e.g., military systems that operate at six and eight times the DS1 rate. At least one manufacturer has a commercial system that operates at 90 Mb/s, twice the DS3 rate. New systems, which take advantage of the high data rates offered by optical communications links, are also deployed or are under development. - Browse Related Terms: access connection, adaptive channel allocation, automatic sounding, basic access, broadband exchange (BEX), Capacity, channel gate, Channelization, circuit transfer mode, common control, common equipment, common-channel interoffice signaling (CCIS), embedded operations channel (EOC), multidestination mode (MD), positioned channel, primary channel, primary rate interface (PRI), restricted channel, secondary channel, statistical multiplexing, T-carrier, terminal
All > Technology > Telecommunications
A passive optical coupler having three ports (three fibers). Note 1: Two isolated inputs may be combined into one output; or one input, into two isolated outputs. Note 2: The amount of coupling loss, usually expressed in dB, between ports is determined by the design and construction of the coupler. [After FAA] Synonyms directional coupler, splitter, tee coupler.
- Browse Related Terms: Amplifier, attenuator, bandwidth (of an optical fiber), medium access unit (MAU), noise current, noise voltage, optical detector, optical junction, photon noise, quantum efficiency, quantum noise, shot noise, source efficiency, spectral responsivity, star coupler, T-coupler, transfer function
All > Technology > Telecommunications
For basic rate access in an Integrated Services Digital Network (ISDN) environment, a user-to-network interface reference point that (a) is characterized by a four-wire, 144-kb/s (2B+D) user rate, (b) accommodates the link access and transport layer function in the ISDN architecture, (c) is located at the user premises, (d) is distance sensitive to the servicing network terminating equipment, and (e) functions in a manner analogous to that of the Channel Service Units (CSUs) and the Data Service Units (DSUs).
- Browse Related Terms: attachment unit interface (AUI), medium interface connector (MIC), medium interface point (MIP), message register leads, originating connection, R interface, S interface, S reference point, T-interface, terminal adapter, Trunk Gateway, U reference point, V reference point, wireline access mode
All > Technology > Telecommunications
See series T junction.
- Browse Related Terms: feeder echo noise, forward echo, matched junction, reflection coefficient (RC), return loss, series T junction, standing wave, standing wave ratio (SWR), T junction, Termination, voltage standing wave ratio (VSWR)
All > Technology > Telecommunications
In Integrated Services Digital Networks (ISDN), the conceptual point dividing NT2 and NT1 functional groupings in a particular ISDN arrangement.
- Browse Related Terms: basic rate interface (BRI), broadband ISDN (B-ISDN), operator service access point (OSAP), operator services, synchronous transfer mode, T reference point, transfer mode, U interface, Wide area network (WAN)
All > Technology > Telecommunications
See T-carrier.
- Browse Related Terms: carrier dropout, characteristic frequency, Modulation, modulator, OC, quieting, T1 (carrier), T1C (carrier), T2 (carrier), T3 (carrier), T4 (carrier), T5 (carrier), Utilization Level
All > Technology > Telecommunications
A full-duplex digital transmission facility that is composed of transmission media (optical or metallic) and regenerators that carry one DS1 signal. [After T1.408-1990]
- Browse Related Terms: air-spaced coaxial cable, equivalent gauge, field wire, fortuitous conductor, metallic circuit, metallic voltage, open wire, rope lay conductor, slope equalizer, symmetrical pair, T1 line, unbalanced line, voltage rating, wireline
All > Technology > Telecommunications
See T-carrier.
- Browse Related Terms: carrier dropout, characteristic frequency, Modulation, modulator, OC, quieting, T1 (carrier), T1C (carrier), T2 (carrier), T3 (carrier), T4 (carrier), T5 (carrier), Utilization Level
All > Technology > Telecommunications
See T-carrier.
- Browse Related Terms: carrier dropout, characteristic frequency, Modulation, modulator, OC, quieting, T1 (carrier), T1C (carrier), T2 (carrier), T3 (carrier), T4 (carrier), T5 (carrier), Utilization Level
All > Technology > Telecommunications
See T-carrier.
- Browse Related Terms: carrier dropout, characteristic frequency, Modulation, modulator, OC, quieting, T1 (carrier), T1C (carrier), T2 (carrier), T3 (carrier), T4 (carrier), T5 (carrier), Utilization Level
All > Technology > Telecommunications
See T-carrier.
- Browse Related Terms: carrier dropout, characteristic frequency, Modulation, modulator, OC, quieting, T1 (carrier), T1C (carrier), T2 (carrier), T3 (carrier), T4 (carrier), T5 (carrier), Utilization Level
All > Technology > Telecommunications
See T-carrier.
- Browse Related Terms: carrier dropout, characteristic frequency, Modulation, modulator, OC, quieting, T1 (carrier), T1C (carrier), T2 (carrier), T3 (carrier), T4 (carrier), T5 (carrier), Utilization Level
All > Technology > Telecommunications
A transportable store-and-forward message-switching system used for rapid deployment in support of tactical forces.
- Browse Related Terms: channel bits, clear message, communications watch, compelled signaling, error-correcting system, forward channel, mail gateway, non-transparent loopback, receive only (RO), routing, store-and-forward (S-F), store-and-forward switching center, Tactical Automatic Digital Switching System (TADSS), Transponder
All > Technology > Telecommunications
The equipment, communications, procedures, and personnel essential to a commander for planning, directing, coordinating, and controlling tactical operations of assigned forces pursuant to assigned missions.
- Browse Related Terms: access system, automated tactical command and control system, combined station, command and control (C2), command line, command menu, command, control, communications, and computer systems (C4S), Emission Control (EMCON), nested command menu, prompt, semiautomated tactical command and control system, tactical command and control (C2) systems, tactical communications system, tactical load
All > Technology > Telecommunications
Communications in which information of any kind, especially orders and decisions, are conveyed from one command, person, or place to another within the tactical forces, usually by means of electronic equipment, including communications security equipment, organic to the tactical forces. Note: Tactical communications do not include communications provided to tactical forces by the Defense Communications System (DCS), to nontactical military commands, and to tactical forces by civil organizations.
- Browse Related Terms: acceptance, certificate hold, command, control and communications (C3), Federal Telecommunications System 2000 service, network management, network security architecture, password length parameter, restriction certificate, security exchange, shadow, signatory authority, tactical communications, Warner exemption
All > Technology > Telecommunications
A communications system that (a) is used within, or in direct support of, tactical forces, (b) is designed to meet the requirements of changing tactical situations and varying environmental conditions, (c) provides securable communications, such as voice, data, and video, among mobile users to facilitate command and control within, and in support of, tactical forces, and (d) usually requires extremely short installation times, usually on the order of hours, in order to meet the requirements of frequent relocation.
- Browse Related Terms: access system, automated tactical command and control system, combined station, command and control (C2), command line, command menu, command, control, communications, and computer systems (C4S), Emission Control (EMCON), nested command menu, prompt, semiautomated tactical command and control system, tactical command and control (C2) systems, tactical communications system, tactical load
All > Technology > Telecommunications
A netted link in which one unit acts as a net control station and interrogates each unit by roll call. Note: Once interrogated, that unit transmits its data to the net. This means that each unit receives all the information transmitted. This is a direct transfer of data and no relaying is involved.
- Browse Related Terms: centralized operation, express orderwire, master station, NCS, noncentralized operation, passive station, point-to-point link, polling, radio relay, relay configuration, Sounding, switched circuit, tactical data information link--A (TADIL--A), Token, tributary station
All > Technology > Telecommunications
A point-to-point data link between two units which provides for simultaneous transmission and reception of data (duplex).
- Browse Related Terms: air-ground worldwide communications system, base communications (basecom), bridge-to-bridge station, combat-net radio (CNR), conference operation, Control Station, military common emergency frequency, net operation, push-to-type operation, semiduplex operation, standby, tactical data information link--B (TADIL--B), transceiver
All > Technology > Telecommunications
A standardized communications link, approved by the Joint Staff, that is suitable for transmission of digital information, and is characterized by standardized message formats and transmission characteristics.
- Browse Related Terms: access control message, address pattern, auto-reply, CAMA, collective routing, FLASH message, mailbox-type facility, mark sequence, Mbone, message body, MIME, minimize, misdelivered block, multi-threaded, origination network, routine message, signaling path, source quench, start-of-heading character (SOH), start-of-text character (STX), system blocking signal, tactical data information link (TADIL), teletypewriter control unit (TCU)