Telecom Terminology Glossary
Below is a dictionary of telecommunications terms.
ATM (Asynchronous Transfer Mode)
Very high-speed transmission technology. ATM is a high bandwidth, low-delay, connection-oriented, packet-like switching and multiplexing technique.
ATSC (Advanced Television Systems Committee)
It’s not really a word, but an acronym for the Advanced Television Systems Committee. ATSC is a committee formed to establish voluntary standards for advanced TV systems, focusing on digital television, broadband multimedia communications standards, and interactive systems. ATSC has 54 members including television networks, producers, trade associations, members of the academic community, plus others.
This is very important and can be confusing for someone new to higher education. In a nutshell, it means that the coursework meets specific academic requirements Programs can be regionally or nationally accredited so check with the Council for Higher Education Accreditation (CHEA) for more information. Most often, tuition assistance is available for regionally accredited colleges and universities and coursework taken from regionally accredited colleges and universities is more readily transferable than that taken from schools that are not regionally accredited.
In a hierarchical telecommunications network the backhaul portion of the network comprises the intermediate links between the core network, or backbone, of the network and the small sub-networks at the "edge" of the entire hierarchical network. For example, while cell phones communicating with a single cell tower constitute a local sub-network, the connection between the cell tower and the rest of the world begins with a backhaul link to the core of the telephone company's network (via a point of presence).
The width of a communications channel. In analog communications, bandwidth is typically measured in Hertz. In digital communication, bandwidth is measured in bits per second (bps).
A short-range wireless connection standard. Its aim is to link a wide range of computers, electronics and telecoms devices. The technology uses a low-power, two-way radio link, which is built into a microchip. The Bluetooth standard is allowing for greater wireless internet capability in the office and for consumers.
In telecommunications, broadband means a wide range of frequencies over which information can be transmitted. A simple way to compare broadband and narrowband Internet connections is to picture a highway. Only one car can travel at a time on a one-lane highway (narrowband). However, when a highway is six or eight lanes wide (broadband), more traffic can drive on the road at the same time. Think back to when you had a dial-up Internet connection. Now think about the Internet today. You have ‘always-on’ data connections that enable you to access multiple media sources and a wide range of information at the same time. That’s broadband.
‘Triple-play’ and ‘quad-play’ are ways that telecom companies package (bundle) their services. While they used to only offer home telephone service, they now provide home phone, Internet connection, television and maybe even cell phone service. Each telecom carrier offers different products and services so their packaging is different. Some even establish relationships with other companies to deliver services. For example, Century Link partners with DIRECTV to offer satellite TV services to its customers. Expect to see more bundling in the future. Who knows, there may even be a quint-play on the horizon.
CDMA (Code Division Multiple Access)
CDMA is a channel access method used by different radio communication technologies- one way to understand CDMA is to think of a party where everyone is talking at the same time. Lots of confusion, right? CDMA assigns different codes to each group of users, so other groups hear just noise-- and tune out.
CLEC - Competitive Local Exchange Carrier
The Telecommunications Act of 1996 opened the door to competition for local phone service. This act mandated that the Incumbent Local Exchange Carriers (ILEC) such as Verizon, Bell South, or SBC provide the necessary interfaces so that CLECs could provide seamless local service. For example, MegaPath is a CLEC.
CPE (Customer Provided Equipment)
Telephone equipment (key systems, PBXs, answering machines, etc.) which live on the customer’s premises.
CSP (Communication Service Provider)
An umbrella term used to describe both traditional providers of communication services (ie: telecom) and alternate providers such as cable TV companies and other over-the-top providers.
A company that is authorized by regulatory agencies to operate a telecommunications system. Examples include AT&T, Alltell, and Verizon.
Central Office (CO)
In almost every neighborhood there is a windowless building that houses the switching equipment that connects your telephone to your neighbor's telephone or routes your call to another central office for long distance calls. This building is called the central office. The central office has switching equipment that can switch calls locally or to long-distance carrier phone offices.
Collection of technologies through which businesses or consumers pay to use software that lives in another company’s data center. The benefit is that server capacity can increase or decrease in response to customer demand, freeing companies from having to invest as much in hardware and ultimately saving them money. This relates to telecommunications because the information in the cloud is accessed through broadband connections. Cloud computing is driving large volumes of new traffic across telecom networks and making businesses increasingly reliant on telecom services.
In telecommunication and computing in general, a connection is the successful completion of necessary arrangements so that two or more parties (for example, people or programs) can communicate at a long distance. Connectivity can be tied to both hardware and software.
The tendency for different technological systems to evolve towards performing similar tasks. A great example of this is smartphones. Not only can you make calls, you can also use them as a personal computer to surf the web, send text messages and monitor your home security system.’
DAC (Digital Analog Converter)
A device which converts digital pulses (i.e.: data) into analog signals so that the signal can be used by analog devices such as phones.
DC Power Plant
Each Central Office houses an AC power plant as well as an AC/DC converter that runs the majority of the telecommunications equipment. Some Central Office Technicians focus on keeping these power plants running efficiently 24/7.
DSL (Digital Subscriber Line)
The technology used between a customer’s premises and the telephone company to support the transport of higher bandwidth digital signals on the copper twisted wire pairs already in place as part of the telephony infrastructure. Also known as generic name signifying the family of Digital Subscriber Line technologies including ADSL, HDSL, VDSL, etc.
DSO, DS1 & DS3 (Digital Signal 0, 1, 3, etc.)
Different levels of digital hierarchy for the amount and speed of data carried on a circuit. The fundamental speed level is DS-0, which is a voice grade channel.
DWDM (Dense Wave Division Multiplexing)
The higher-capacity version of WDM, which is a means of increasing the capacity of fiber-optic data transmission systems through sending many wavelengths of light down a single strand of fiber.
A portable mobile broadband adapter connected to a laptop or PC via a USB port.
Ethernet is a standard for using various transmission media, such as coaxial cables, unshielded twisted pairs, and optical fibers.
A facilities person assigns the cable or fiber pair numbers. The facilities assignment refers to where the telephone number starts in the central office and the route it takes from the central office to the end address (includes those boxes you see on the side of the street).
Femtocells enhance coverage and capacity inside buildings which means fewer dropped calls. This has potential to allow cell phone calls to travel over the internet.
Fiber / Fiber Optic Cable
Transmits light signals along glass strands, permitting 10-100 times faster transmission than traditional copper wire. What this means to the consumer, is faster, more efficient cell phones and Internet connections. You may hear FTTH (fiber to the home), FTTP (fiber to the premises). Those terms simply mean – how close the fiber comes to a building, house…end user. The closer it comes, the faster the connection.
A firewall is a part of a computer system or network that is designed to block unauthorized access while permitting authorized communications. It is a device or set of devices which is configured to permit or deny computer based application upon a set of rules and other criteria.
A rack to which telecommunications equipment is mounted. You will see these in Central Offices.
The standard for high-speed data communications, offering users transmission speeds of 2.048 megabits per second and higher. It allows faster speeds than the X.25 packet switching standard because it does away with elaborate error-correction and routing information. Its main application is interconnecting local area networks.
HCS (Hierarchical Cell Structure)
Hierarchical Cell Structure: the architecture of a multi-layered cellular network where subscribers are handed over from the macro to the micro to the pico layer, depending on the current network capacity and the needs of the subscriber.
A technology that provides better audio quality by delivering at least twice the sound range (wideband) of a traditional (narrowband) telephone call.
HDSL (High Bit Rate Digital Subscriber Line)
This is digital access technology typically used by businesses. It requires two copper wire pairs (or in some cases fiber) but doesn’t require complex engineering and installation.
HSPA (High Speed Packet Access)
Often referred to as 3.5G, this is an extension to the original 3G standard providing significantly higher data rates. HSDPA (downlink) can provide theoretical maximum downlink speeds of 168 Mbps. HSUPA (uplink) supports maximum uplink speeds of 22 Mbps.
IPTV (Internet Protocol Television)
Digital television delivered over the Internet. It can be accessed through a closed or public network, with a computer or a set-top box capable of processing the video streams. This is in direct competition with traditional cable and broadcast television. IPTV can be bundled with VoIP and Internet access for a triple play service, increasing the competition that other television providers face.
This is an incredibly important part of the communications industry. Roughly 25% of all telecom workers are involved with telecom infrastructure – in its simplest terms, infrastructure includes the pieces and parts that make sophisticated communications systems work.
2TP (Layer 2 Tunneling Protocol)
Layer 2 Tunneling Protocol is an IETF (Internet Engineering Task Force) standard tunneling protocol for VPNs. ISPs use this to provide secure, node to node communications in support of multiple, simultaneous tunnels in the core of the internet or IP based networks.
LAN (Local Area Network)
Locally owned and administered network for data communications that provides a relatively high bandwidth over a limited geographic area for communication between attached devices (typically personal computers and servers). LANs are most often at a customer site. An Ethernet is a common example of a type of LAN.
LATA - Local Access and Transport Area
Geographic area covered by one or more local telephone companies, which are legally referred to as local exchange carriers (LECs). A connection between two local exchanges within the LATA is referred to as intraLATA. A connection between a carrier in one LATA to a carrier in another LATA is referred to as interLATA. InterLATA is long-distance service. The current rules for permitting a company to provide intraLATA or interLATA service (or both) are based on the Telecommunications Act of 1996.
LTE (Long Term Evolution)
LTE is a broadband access technology that enhances the ability of mobile users to access larger amounts of data. LTE operates on a lower frequency of 700 MHz giving it enhanced signal range and building/obstacle penetration. AT&T and Verizon Wireless are building their 4G networks with LTE technology. This is a big deal because for the most part, consumers want more and more data. In fact, a recent IBM report shows that when people are asked what they would be least likely to cut back on to save money - people chose mobile phones and broadband Internet only after their homes.
MMS (Multimedia Messaging Service)
The standard in mobile messaging services, adding photos, pictures and audio to text messages.
MUX - Mulitplex
To transmit two or more signals over a single channel. In the world of CAT5 the explosion of choices that digital TV is bringing the multiplex means to offer subscribers a choice of various starting times for movies and events.
Wireless high-speed internet access through a portable modem, telephone or other device.
A telecommunications network is a collection of terminals, links and nodes which connect together to enable telecommunication between users of the terminals. Networks may use circuit switching or message switching. Each terminal in a network must have a unique address so messages or connections can be routed to the correct one.
Network Operations Center (NOC)
A network operations center (or NOC, pronounced "knock") is one or more locations from which control is exercised over a computer, television broadcast or telecommunications network.
Refers to all of the physical cabling and supporting infrastructure (such as conduit, cabinets, tower or poles), and any associated hardware (such as repeaters) located between a demarcation point in a switching facility to another switching facility or to a customer premises.
Private Branch Exchange Digital or analog telephone switchboard located on the customer premises and used to connect private and public telephone networks.
PBX (Private Branch Exchange)
A private (as in owned by the telephone company) exchange (as in the Central Office). A PBX is a small version of the phone company’s larger central switching office. In other words, an analog telephone switchboard located on the customer premises and used to connect private and public telephone networks.
A general term for all equipment used by a telephone company to provide telecommunications services. In the telecom business, plant comes in two variations – inside and outside plant. Inside is in a building. Outside is outside the building – on poles, in the ground.
At a customer’s location/premises. This could be anything from an office to a factory to a home.
RBOC (Regional Bell Operating Company)
There are seven (also known as Baby Bells) which own the local exchange carriers in the US following the divestiture/breakup of AT&T ('Ma Bell') in 1984.
Check out this CenturyLink video to better understand Remote Access.
Telecommunications companies that purchase network capabilities from external sources and resell those services to private households or businesses.
Routing / Router
The process of selecting paths in a network along which to send network traffic. Routers are the equipment used to make this happen.
SDH (Synchronous Digital Hierarchy)
SDH and SONET are essentially the same thing. Standard multiplexing protocols that transfer multiple digital bit streams over optical fiber using lasers or light-emitting diodes (LEDs). Lower rates can also be transferred via an electrical interface.
SONET (Synchronous Optical Network)
A family of fiber optic transmission rates created to provide the flexibility needed to transport many digital signals with different capacities and to provide a design standard for manufacturers.
SS7 (Signaling System Number 7)
An international, standard, set of telephone signaling protocols which are used to set up most of the world's public switched telephone network telephone calls. The main purpose is to set up and tear down telephone calls.
Satellite telecommunications establishments are made up mostly of government and private organizations that transmit a variety of data through satellites, including photos of the earth, messages to and from public safety officials, and a variety of other information. Direct-to-home satellite TV providers, however, are classified with wired telecommunications.
Service Management System (SMS)
A highly reliable computer system that is connected to telecommunications Network systems.
A smartphone is a mobile phone on steroids. It offers more advanced computing and connectivity than a contemporary basic ‘feature phone’. Smartphones can be thought of as handheld computers integrated within a mobile telephone.
The joining of two or more cables together by splicing the conductors together. In copper wire telephone cables, splicing is on a mechanical basis and pair-to-pair, with the pairs organized by binder groups and color codes. In optical fiber cables, the splicing is fiber-to-fiber, with the fibers organized by ribbon or colored buffer tube and color code. Fiber optics splicing may be either mechanical splicing or fusion splicing.
Switch - switching
A device that channels incoming data from any of multiple input ports to the specific output port that will take the data toward its intended destination. In the traditional circuit-switched telephone network, one or more switches are used to set up a dedicated though temporary connection or circuit for an exchange between two or more parties. On an Ethernet, local area network (LAN) a switch determines from the physical device (Media Access Control or MAC) address in each incoming message frame which output port to forward it to and out of. In a wide area packet-switched network such as the Internet, a switch determines from the IP Address in each packet which output port to use for the next part of its trip to the intended destination.
Transmitting signals over a distance in order to communicate. The classic ‘tin can’ telephone is a very simple telecommunications system. Emerging technologies have brought us far from that model. Today’s communication could be via telephone, television, radio, satellite, wireless network, computer network, telemetry, or other means. These technologies, plus many more are converging—you can access the Internet, play videos, or track your children's movements via global positioning system (GPS) technology on your cell phone—so the lines between telecommunications and other industries like computer hardware, application software, consumer electronics and entertainment are getting blurrier all the time.
Networks of leading-edge technologies such as fiber optic systems, satellites, wireless, telephony, and cable, which are connected to computers that allow organizations and individuals throughout business and industry to communicate instantaneously around the world.
A device that receives calls and allows them to be transmitted to the next local calling area, thus avoiding toll or access charges.
Trunk / Trunking
A communication line between two switching systems. The term switching system typically includes equipment in a Central Office and PBXs. A tie trunk connects PBXs. Central office trunks connect a PBX to the switching system at the Central Office.
The acronym VIVID includes each component of the evolving communications industry: Voice, Information, Video, Infrastructure & Data.
VOIP (Voice over Internet Protocol)
Harnesses the power of broadband internet connections to allow consumers access to telephone services over the internet. In other words, your words get converted into data signals and travel over the internet. Once they get to their destination, they are converted from data signals back into analog signals and transmitted. Upgrades in technology helped combat problems with early VoIP, such as poor quality and availability of service. Today’s VoIP is a viable competitor to traditional telephony. As businesses continue to cut costs and limit travel budgets, expect to see the use of VoIP increase.
VoLTE, or Voice Over LTE is similar to VoIP- but goes one step further. Instead of using the hardware at the ends of the call (the phones), VoLTE offloads the heavy lifting to the network- creating VoIP HD. Beyond a crisp and clear sound, VoLTE includes the ability to cancel echoes and background noise on the back end, not the handset itself *.
Audible communication over a traditional land-line, wireless cellular or smart phone or even through a computer via VOIP.
Wide Area Network (WAN)
A computer or communications network that covers a geographic area which is larger than a business campus. Usually, the dividing line between a local or campus network and an Wide Area Network is a router. On the local or campus side, the transmission lines in a network (copper or fiber) are usually owned by the enterprise. On the WAN side, the lines are typically owned by a carrier and leased to an enterprise.
3G and 4G
These terms refer to third- and fourth-generation cellular wireless capabilities. 3G and 4G networks allow mobile and smart phone users to access more information and services on their devices faster. It’s because of these technological advances that you can video chat, watch Internet TV, play online games, download videos and listen to streaming music on your phone. Simply put, 3G and 4G allow you to do more. Both 3G and 4G—now enhanced by LTE technology—are available across most of the U.S. today. The major difference between the two is speed. In general, 4G LTE networks are much faster than 3G LTE networks.