VoIP Glossary

ATA:

Analog telephone adapter. Converts analog to digital to transmit over the Internet. ATA is the simplest way to connect standard phone lines to a computer to use VoIP phone services.

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circuit-switched technology:

Where a dedicated path from caller to receiver is reserved for their entire conversation. In contrast, a VoIP system uses packet-switching, treating voices as data and sending the information over shared data networks before converting it back into audio.

codecs:

Coder-decoders. Converts audio into compressed digital format for transmission on VoIP phone services and then back to uncompressed audio when it reaches its destination.

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CTI:

Computer Telephony Integration. VoIP works with advanced CTI applications, such as call center management, to prioritize incoming calls based on caller identity and to bring up callers' account information on-screen when calls are answered.

data compression:

Reduces size of VoIP phone calls before they are transmitted.

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endpoint:

Where the data from a VoIP phone call is supposed to arrive.

H.323:

Protocol for video compression originally used in videoconferencing that can transmit real-time audio and video data information over IP networks.

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internet telephony:

Another term for VoIP. Allows you to make real-time voice, fax, and video calls over the Internet. Small businesses use it to reduce long distance and international calling costs.

IP phone:

Regular phone that connects directly to a router using a wider connector for an Enternet connection rather than a standard phone jack.

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jitter:

Shifts in data transmission that adversely affects VoIP phone service quality.

KSU:

Key System Unit. Central control device for traditional phone systems that contains the electronics detailing which lines direct to which phones.

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KSU-less systems:

Inexpensive system designed for very small businesses to provide many of the features of a multi-line traditional phone system without connecting to a central control unit.

LAN:

Local Area Network. Local network for communication between computers. Multiple computers can connect to a single LAN and data can be transmitted very quickly. If a company has multiple locations – branches, telecommuters, remote sales offices – connected to a LAN, it can easily set up a VoIP system.

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latency:

The time it takes a packet of data to get from one point to another. Also called delay.

MAC:

Move, Add, and Change process. You can configure almost all VoIP phone systems through a web interface. Network administrators only need to maintain one network to move existing lines to new locations, add new lines, and change existing lines from one employee to another.

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MGCP:

Media Gateway Control Protocol. Standard for converting audio signals into data packets carried over a network. Since VoIP phones aren’t connected to specific switches, they use processors to work independently from a central switching location.

NANP:

North American Numbering Plan. The system that distributes phone numbers throughout the country. VoIP phone service reads phone numbers as IP addresses rather than NANP to route phone calls.

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packet:

The individual units of data routed from the data source to its destination.

packet loss:

Data that doesn't reach its intended destination when network traffic is heavy.

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packet-switching:

Technology that breaks messages into individual packets for VoIP phone service. Each packet is sent over the Internet individually – and often out of order – and reforms at its destination.

payload:

A section of a file transmitted in a packet.

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PBX:

Private Branch Exchange. In-house telephone switching system that interconnects telephone extensions to each other, as well as to the outside telephone network. The equipment switches internal and external calls and allows users to share multiple external phone lines. Many PBX systems can be IP-enabled with software upgrades and minor hardware additions to handle VoIP phone services.

processor drain:

The drop in quality of VoIP phone service as you open more applications on your computer.

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protocol:

Defines how hardware and software devices connect to each other and your network using VoIP. H.323 is the most common protocol for VoIP phone services.

PSTN:

Public Switched Telephone Network. This circuit-switched network creates a dedicated, high-quality connection for phone calls.

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QoS:

Quality of Service. Maintains a dedicated amount of bandwidth for voice calls by giving voice data a higher priority as it is trafficked through the network. If there is network congestion, VoIP data is routed through first so call quality does not suffer.

redundancy:

Companies that have backup power systems in place can keep their PBX running, and VoIP within the main office will continue to operate even if the data network is unavailable.

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sampling:

Measuring the value of an analog signal at regular intervals, typically millions of times per second, and encoding them into a digital format for VoIP phone services.

SIP:

Session Initiation Protocol. Establishes sessions over your IP network for VoIP functions.

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soft phone:

Software that allows laptops to function as IP-enabled phones to access VoIP service when on the road.

soft switch:

Separates network hardware from software to effectively route voice and data over the Internet for VoIP phone services.

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VoIP:

Voice over Internet Protocol. A phone system technology that sends regular voice calls over a computer network instead of traditional phone lines. It requires a standard phone, an adapter, a subscription to a VoIP phone service, and a broadband connection. Calls are sent over the Internet as data until it approaches the person you’re calling. Calls are then returned to audio before traveling over standard phone lines.

VoIP phone systems:

The actual VoIP phone services equipment installed at your business that routes internal calls over your computer network. You can combine multiple offices on a single phone system and eliminate long-distance calling charges between them.

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VPN:

Virtual Private Network. Uses encryption to transmit data over the Internet to keep data private and ensure only authorized users access the network. For businesses that connect to the company network using VPN, employees can use VoIP phone services to make phone calls from outside the office to save money.

WAN:

Wide Area Network. Large geographical area network – usually two or more LANs – that allow computers to connect to each other over various distances using satellite communications or telephone systems. If a company has multiple locations – branches, telecommuters, remote sales offices – connected to a WAN, it can easily set up a VoIP system.

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