Glossary of Terms

List of industry acronyms and definitions


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2FA (Two Factor Authentication) A security system that requires two separate, distinct forms of identification in order to access something.

2WV (Two Way Voice) The ability to send and receive voice communications simultaneously. Also known as Full Duplex.

8XX (Toll-Free Inbound to Customer) see Toll-Free

8YY (Toll-Free Outbound from Customer) see Toll-Free

A2P 10DLC (Application to Person messaging) A system in the United States that allows businesses to send Application-to-Person (A2P) type messaging via standard 10-digit long code (10DLC) phone numbers.

ACD (Automated Call Distribution) A telephony system that automatically receives incoming calls and distributes them to an available agent. This frequently refers to call center queues, but also applies to hunt groups.

ACL (Access Control List) A set of rules that grant or deny access to certain digital environments

API (Application Programming Interface) A set of functions and procedures allowing the creation of applications that access the features or data of an operating system, application, or other service.

ATA (Analog Telephony Adapter) A small device designed to adapt the analog signals of older telephony devices for VoIP or SIP communications via Ethernet or WiFi.

Atlas The agent-facing portal provided by Inteliquent meant to build sales proposals and orders, manage the service delivery process, and assist customers.

CAP (Customer Administration Portal) The user-facing portal provided by Inteliquent and branded for a partner's business meant to manage the PBX. This is accessible through an Internet connection and is not device dependent.

CIC (Carrier Identification Code) A unique four-digit code given by the North American Numbering Plan Administrator (NANPA) to carriers and other entities. As a unique identifier, a CIC is used for billing purposes and routing calls over the interconnected public switched telephone network (PSTN).

CNAM (Caller NAMe) The caller ID name that is displayed on an incoming phone call.

CPaaS (Communications Platform as a Service) A cloud-based platform that enables developers to add real-time communications features to their own applications without needing to build backend infrastructure and interfaces.

CSR (Customer Service Record) The records that a service provider holds with information regarding a business's account. This includes phone numbers, activity history, business and personal information like name and address, and account number.

Dial Tone A sound produced by a telephone that indicates that a caller may start to dial. In a UC device, this is often a locally stored .wav file and does not necessarily indicate connection to a larger telephone network.

DID (Direct Inward-Dialing number)  Also known as a phone number, this is the ten digit number used by the PSTN to route calls to specific PBX endpoints. Also known as "TN" or "10DLC".

Direct Routing A way to provide a PSTN connection to service users so that they can make and receive external phone calls on any device using that service.

DNC (Do Not Call) A registry of phone numbers in the United States that telemarketers are prohibited from calling in most circumstances

DND (Do Not Disturb) A setting in a phone system that automatically denies inbound calls, frequently treating the line as busy (with the associated call forwarding rules).

DNIS (Dialed Number Identification Service) A service sold by telecommunications companies to corporate clients that identifies the originally dialed telephone number of an inbound call. The client may use this information for call routing to internal destinations or activation of special call handling. 

DS x (Digital Signal Level x) A discrete signal that is being used to represent data as a sequence of discrete values; at any given time it can only take on, at most, one of a finite number of values. "DS0" is a 64 Kb/s data and voice channel, "DS1" is a T1 equivalent channel, and "DS3" is a T3 equivalent, for example.

DWDM (Dense Wavelength Division Multiplexing) An optical multiplexing technology used to increase bandwidth over existing fiber networks. DWDM works by combining and transmitting multiple signals simultaneously at different wavelengths on the same fiber.

E911 (Enhanced 911) In order to deliver emergency help more quickly and effectively, the carriers and public safety entities are upgrading the 911 network on a regular basis. For example, most 911 systems now automatically report the telephone number and location of 911 calls made from wireline phones, a capability called Enhanced 911, or E911.

FCC (Federal Communications Commission) An independent Federal regulatory agency responsible directly to Congress. Established by the Communications Act of 1934, it is charged with regulating interstate and international communications by radio, television, wire, satellite, and cable.

FG-D (Feature Group D) A type of telecommunication trunk used to provide "equal access" capability from telecommunication carriers and central offices (where the switching equipment is located and customer lines are connected and terminated) to the access tandem.

Full Duplex Data that can be transmitted in both directions on a signal carrier at the same time.

GIG Wave A circuit operating on a DWDM wavelength with bandwidth of 1 gigabit.

HIPAA (Health Insurance Portability And Accountability Act) Legislation which provides security provisions and data privacy, in order to keep patients' medical information safe.

Hosted UC (Hosted Unified Communications) UC services that are provided from the cloud, rather than from equipment on premise to the user.

IoT (Internet of Things) The IoT can be described as an extension of the internet and other network connections to different sensors and devices — or “things” — affording even simple objects, such as lightbulbs, locks, and vents, a higher degree of computing and analytical capabilities.

IP (Internet Protocol) The set of rules governing the format of data sent via the internet or local network. In essence, IP addresses are the identifier that allows information to be sent between devices on a network: they contain location information and make devices accessible for communication.

IPX (Internetwork Packet Exchange) A networking protocol originally used by the Novell NetWare operating system and later adopted by Windows. IPX has a similar function to the IP protocol and defines how data is sent and received between systems.

IVR (Interactive Voice Response) An automated phone system technology that allows incoming callers to access information via a voice response system of pre recorded messages without having to speak to an agent, as well as to utilize menu options via touch tone keypad selection or speech recognition to have their call routed to specific departments or specialists.

IXC (Inter eXchange Carrier) A telephone company that provides connections between local exchange s in different geographic areas.

Kari's Law Legislation in the United States that requires multi-line telephone systems (MLTS) to route 9-1-1 emergency service calls through the phone system automatically.

LAN (Local Area Network) A computer network that spans a relatively small area. Most often, a LAN is confined to a single room, building or group of buildings, typically through Ethernet cables. One LAN can be connected to other LANs over any distance via telephone lines and radio waves.

LEC (Local Exchange Carrier) A regulatory term in telecommunications for the local telephone company. In the United States, wireline telephone companies are divided into two large categories: long distance (interexchange carrier, or IXCs) and local (local exchange carrier, or LECs).

LNP (Local Number Portability) Also known as number portability and number porting, enables end users to keep their DID or telephone number when switching from one telecommunications service provider to another.

MM4 An interface used to exchange messages between two MMSCs for MMS messaging traffic.

MMS (Multimedia Message Service) A standard way to send messages that include multimedia content to and from a mobile phone over a cellular network. Users and providers may refer to such a message as a PXT, a picture message, or a multimedia message.

MMSC (Multimedia Message Switching Center) This center handles MMS operations like forwarding multimedia messages until they’ve reached their desired destinations.

MSP (Managed Service Provider) A company that remotely manages a customer's IT infrastructure and/or end-user systems, typically on a proactive basis and under a subscription model.

MLTS (Multi-Line Telephone System) A phone system that provides communication over multiple lines.

N11 These codes are used to provide three-digit dialing access to special services. In the U.S., the FCC administers N11 codes. The FCC recognizes 211, 311, 511, 711, 811 and 911 as nationally assigned, but has not disturbed other traditional uses.

NG911 (Next Generation 911) An initiative aimed at updating the 911 service infrastructure in the United States and Canada to improve public emergency communications services in a growingly wireless mobile society. In addition to calling 911 from a phone, it intends to enable the public to transmit text, images, video and data to the 911 center The initiative also envisions additional types of emergency communications and data transfer.

Off-Net A call that originates and terminates on different networks.

On-Net When your call or message originates on your home operator's network and terminates to another number that resides with your operator. In a UC environment, the on-net call often does not leave the PBX.

OTT (Over The Top) Providing service over a private connection, such as PSTN or the Internet. OTT services may require the assistance of the service provider for extensive troubleshooting.

P2P (Peer to Peer) In a pure peer-to-peer application architecture no central servers are required, whereas traditional SIP telephony networks have relied on using centrally deployed and managed SIP servers, in analogy to the centralized switching architecture of the public switched telephone network (PSTN)

PBX (Private Branch eXchange) A private telephone network used within a company or organization. The users of the PBX phone system can communicate internally (within their company) and externally (with the outside world), using different communication channels like VoIP, ISDN or analog.

PCI (Payment Card Industry) Compliance The set of requirements used to direct businesses on how to maintain a secure network, as well as how to store and transmit customers' credit card information when a card is used in a purchase transaction.

PoE (Power over Ethernet) A device that receive enough power to be usable through the same ethernet cable used to connect it to the LAN.

POI (Point of Interface) In telecommunications a point of interface (POI) is used to show the physical interface between two different carriers, such as a local exchange carrier (LEC) and a wireless carrier, or an LEC and an IntereXchange Carrier (IXC). This demarcation point often defines responsibility as well as serving as a point for testing. In many cases, a POI exists as a point of demarcation within an LEC building, and is established under "co-location" agreements. A long distance, wireless, or competitive local carrier "rents" space at the local telephone (usually tandem switch) location.

POP (Point of Presence) A demarcation point, access point, or physical location at which two or more networks or communication devices share a connection.

PSAP (Public Safety Answering Point) A local emergency 911 center, where emergency calls are answered and specific services are dispatched. There are roughly 6100 primary and secondary PSAPs in the U.S.

PSTN (Public Switched Telephone Network) This system 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.

QoS (Quality of Service) The description or measurement of the overall performance of a service, such as a telephony or computer network or a cloud computing service, particularly the performance seen by the users of the network. To quantitatively measure quality of service, several related aspects of the network service are often considered, such as packet loss, bit rate, throughput, transmission delay, availability, jitter, etc.

RAY BAUM'S Act Legislation that highlights the importance of geographic location in managing emergency situations. When first responders have access to a precise location they are better able to deliver emergency services, improving emergency outcomes and saving lives. 

RespOrg (Responsible Organization) It refers to a carrier that owns and manages toll-free numbers. As the name suggests, a RespOrg is tasked with registering and indexing its toll-free numbers in the 800 database. 

Rest API (Representational State Transfer Application Programming Interface) An architectural pattern describing how distributed systems can expose a consistent interface. For example, you can search for something and get a result back without the need to log in for every query.

RLEC (Rural Local Exchange Carrier) These exchange carriers are local telecom companies responsible for providing the wired PSTN telephone services in their defined geographical zone.

SaaS (Software as a Service) A software distribution model in which a service provider hosts applications for customers and makes them available to these customers via the internet.

SBC (Session Border Controller) A network element deployed to protect SIP based voice over Internet Protocol (VoIP) networks.

Seat A set of services for a user of the UC or UCaaS system. Seats are the elementary unit of a UC PBX.

SIP (Session Initiation Protocol) A TCP/IP-based network protocol which can be used to establish and control communication connections of several subscribers. SIP is often used in Voice-over-IP telephony to establish the connection for telephone calls.

SIP Trunking A voice over Internet Protocol (VoIP) technology and streaming media service based on the Session Initiation Protocol (SIP) by which Internet telephony service providers (ITSPs) deliver telephone services and unified communications to customers equipped with SIP-based private branch exchange (IP-PBX) and unified communications facilities.

SLA (Service Level Agreement) A document (physical or digital) that defines the level of service you expect from a vendor, laying out the metrics by which service is measured, as well as remedies or penalties should agreed-on service levels not be achieved.

SLA (Shared Line Appearance) The sharing of a VoIP phone number across multiple devices. Through a line thusly shared, users can answer incoming calls, retrieve voicemail, and place outbound calls as the other line.

SMPP (Short Message Peer-to-Peer) A protocol used by the telecommunications industry for exchanging SMS messages over the internet, mainly between Short Message Service Centers (SMSC). The protocol is a level-7 TCP/IP protocol, which allows fast delivery of SMS messages.

SMS (Short Message System) This is the protocol used to send text messages to mobile phones. Commonly known as text messaging. See also MMS.

SMSC (Short Message Service Centers) This center handles SMS operations like forwarding text messages until they’ve reached their desired destinations, and storing texts temporarily if the destination is unavailable. Wireless network operators connect SMSCs through SMS gateways, which act as a  transmission between the two SMSCs.

SOC2 (System and Organization Controls 2) An auditing procedure that ensures your service providers securely manage your data to protect the interests of your organization and the privacy of its clients. For security-conscious businesses, SOC 2 compliance is a minimal requirement when considering a SaaS provider.

SS7 (Signaling System 7) a set of telephony signaling protocols developed in 1975, which is used to set up and tear down telephone calls in most parts of the world-wide public switched telephone network (PSTN). The protocol also performs number translation, local number portability, prepaid billing, Short Message Service (SMS), and other services.

SSO (Single Sign On) A system to provide access to multiple website or clients with a single username and password.

STSH/SS (STIR/SHAKEN) A suite of protocols and procedures intended to combat illegal caller ID spoofing on public telephone networks. STIR stands for Secure Telephone Identity Revisited and SHAKEN stands for Secure Handling of Asserted information using toKENs.

TCP/IP A set of rules that governs the connection of computer systems to the internet.

TDM (Time Division Multiplexing) A method of transmitting and receiving independent signals over a common signal path by means of synchronized switches at each end of the transmission line so that each signal appears on the line only a fraction of time in an alternating pattern.

TF (Toll-Free) A direct telephone line or number (such as an 800 number) for a long distance call that is not charged to the caller.

TFN (Toll-Free Number) see TF

TN (Telephone Number) see DID

TSP (Tandem Switching Provider) Any Interexchange Carrier, end user, or other access provider that provides tandem switching functions for switched transport services.

UC (Unified Communications) Bringing together multiple communication services, such as telephone calls, voicemail, chat, fax, email, and conferencing.

UCaaS (Unified Communications as a Service) A version of Hosted UC that is managed by a CPaaS and provided to a customer on a monthly recurring charge.

ULC (Underlying Carrier) A third party vendor/carrier (upstream, or downstream depending on the call direction). This term would be commonly heard in the context referring to outbound calling/termination.

VAR (Value Added Reseller) A firm that enhances the value of third-party products by adding customized products or services for resale to end-users.

VLAN (Virtual Local Area Network) A custom network created from one or more existing LANs. It enables groups of devices from multiple networks (both wired and wireless) to be combined into a single logical network.

VLEC (Virtual Local Exchange Carrier) A voice service carrier that uses he Internet to establish network interconnection with other LECs to enable local exchange telecommunications services.

VM (Voicemail) A centralized electronic system that can store messages from telephone callers.

VoIP (Voice Over IP)  Method of providing voice telecommunication services over an Internet Protocol. See also OTT.

VPN (Virtual Private Network) An encrypted connection over the Internet from a device to a network. The encrypted connection helps ensure that sensitive data is safely transmitted. It prevents unauthorized people from eavesdropping on the traffic and allows the user to conduct work remotely.

WAN (Wide Area Network) A telecommunications network that extends over a large geographical area for the primary purpose of computer networking. Wide area networks are often established with leased telecommunication circuits.