Telecom Dictionary

ACD - Average Call Duration

ASR - Answer-Seizure Ratio. The ratio of successfully connected calls to attempted calls.

ALOC - Average Length of Call (sometimes ACD)

ANI Automatic Number Indentification (sometimes Source Number)

Billing Increment - A call duration measurement unit, expressed in seconds. For example a 30/1 billing increment means that the first 30 seconds always are billed and then each second it is used, each second is billed.

CDR Call Detail Record. Call Detail Record Computer record containing data unique to a specific call.

Codec - Compression-decompression. A technique used to compress/decompress speech or audio signals. The most popular ones in VoIP are G.711, G.721 and G.729.

DID Direct Inward Dialing; A specially configured phone line from the telephone company that allows for dialing inside a company directly without having to go through an attendant.

DN Destination Number

DNIS Dialed Number Identification Service

Domestic Call - Any call that originates (starts) and terminates (ends) within the United States (country).

Dynamic Routing - A procedure for sending calls across a network by which if a trunk group fails, the system will automatically re-route call to next trunk group in routing tables (some time call also route advance). As opposed to static routing where call is sent along pre-programmed trunk group.

Gateway In IP telephony, a network device that converts voice and fax calls, in real time, between the public switched telephone network (PSTN) and an IP network. The primary functions of an IP gateway include voice and fax compression/ decompression, packetization , call routing, and control signaling. Additional features may include interfaces to external controllers, billing systems, and network management systems.

H.323 A standard approved by the International Telecommunication Union (ITU) in 1996 to promote compatibility in videoconference transmissions over IP networks

International Calls - Calls that originate in one country and terminate in another country.

Interstate Calls - State-to-State Calls that originate in one state and terminate in another state.

Intrastate Calls - In-State Calls that originate and terminate within the same state.

IVR Interactive Voice Response

Jitter Jitter is a measure of the variability over time of the latency across a network. A very low amount of jitter is important for real-time applications using voice and video.

LATA Local Access Transport Area. A LATA is a geographical area in the US where a local telephone company may carry both local calls and toll calls that do not leave the LATA. LATAs were created when Judge Green broke up the AT&T monopoly in 1984.

Latency The amount of time it takes a packet to travel from source to destination. Together, latency and bandwidth define the speed and capacity of a network

LCR Least Cost Routing.

NPA-NXX North American phone numbers are in the format (where N is any digit from 2-9, and X from 0-9):
NPA-NXX-XXXX
Specifically:
NPA identifies the 3-digit Numbering Plan Area (Area Code)
NXX identifies the Central Office (aka. Exchange) within the NPA
XXXX identifies the Station within the NXX

POSA Point-of-Sale Activation

PIN - Personal identification number.

PDD Post Dialing Delay. Time between the start of a call and the time the phone starts ringing.

QoS -Quality of Service. On the Internet and in other networks, Quality of Service (QoS) is the idea that transmission rates, error rates, ASR*ACD, and other characteristics can be measured, improved, and, to some extent, guaranteed in advance

RTP - Real-time Transport Protocol. Real-time transport protocol - The Internet-standard protocol for the transport of real-time data, including audio and video. RTP is used in virtually all voice-over-IP architectures, for videoconferencing, media-on-demand, and other applications. A thin protocol, it supports content identification, timing reconstruction, and detection of lost packets.

RTR Real Time Routing.

SIP - Session Initiation Protocol. Protocol for initiating an interactive user session that involves multimedia elements such as video, voice, chat, gaming, and virtual reality.

Soft-switch is a central device in a telephone network which connects calls from one phone line to another, entirely by means of software running on a computer system.

T1 (also referred to as DS1) is a standard for digital transmission over phone lines at 1.544 Mbps. It is split into 24 channels of 64Kbps each. In the original standard, signalling was inband (robbed bit signalling). N ow T1s are often "clear channel" and all bits are available for data.

TDM - Time-division multiplexing is a method of putting multiple data streams in a single signal by separating the signal into many segments, each having a very short duration. Each individual data stream is reassembled at the receiving end based on the timing.

TG Trunk Group.

TF Toll-free numbers are numbers that begin with one of the following three-digit codes: 800, 888, 877, or 866 (for USA). Toll-free numbers allow callers to reach businesses and/or individuals without being charged for the call. The charge for using a toll-free number is paid by the called party (the toll-free subscriber) instead of the calling party.

VoIP - Voice over IP. Voice over Internet Protocol. The technology used to transmit voice conversations over a data network using the Internet Protocol