Glossary of VoIP terms
Acoustic Echo Echo that is the result of feedback that is generated on any phone or speaker phone or headset from the speaker to the microphone. (also see Line Echo)
Attendant (Auto Attendant) An automatic response system, such as a voice presenting options such as press 2 for sales, 5 for Lisa, etc., which handles incoming calls and sends them to the appropriate phone or message.
Attenuation (also referred to as loss) is a term that occurs with any type of signal, (digital or analog) and refers to the reduction in the strength of the signal, which is natural consequence of that signal traveling over the specific medium for long distances.
Backbone A high speed fiber network with a large capacity that connects major cities throughout the world.
Bandwidth Usually measured in 1000 bits per second (kbps), it is the amount of data that can be carried from one point to another in a given time period.
Baud One signaling element per second, not to be confused with bits per second.
BOYD Bring Your Own Device Some VoIP providers allow a person to supply their own equipment or ATA.
CDR Call Record Detail Details about a specific call that includes duration, origination, destination, and billable information, as well as other pertinent information.
Cloud Communications Cloud refers to the Internet. Cloud Communications uses the Internet as a way to have users connect to host equipment at a remote location which then connect to other users allowing phone calls. Synonymous with hosted VoIP or Internet Phone Service.
Codec Normally used to reference to converting analog signals to digital or digital signals to analog. It can be used in conjunction with compression software to compress and decompress these signals to varying degrees.
CPE Customer Premises Equipment Equipment at the customers location that converts the digital signal back to voice.
CSU/DSUChannel Service Unit/Data Service Unit A hardware device usually associated with a T1 that acts as an interface and converts data frames from a LAN to a WAN topology.
CSR Customer Service Record A document required for all phone numbers that will show information that is tied to that number including services, billing activity, associated address and service orders.
Data Usually treated as a synonym for information, but when used as a description for network topology refers to all traffic other than voice.
Data Transfer Rate The speed of travel of a given amount of data from one place to another.
DHCP Dynamic Host Control Protocol A communications protocol that lets network administrators supervise and distribute IP addresses from a central point to each computer or device on a network.
DID Direct Inward Dialing A service that allows an enterprise to allocate individual phone numbers to each person within its PBX system.
DSL Digital Subscriber Line Phone technology that allows a broadband internet digital connection to be carried over existing copper phone lines, while still allowing the phone service carry analog signals over the same line.
DTMF Dual Tone Multi-frequency Also known as Touchtone, it is the signal generated when you press a telephone's touch keys that is sent to the telephone company. These signals are actually two tones of a specific frequency designed so that a voice cannot duplicate them. The ability for interactive telephone menus to work correctly across different networks and phone systems is due to the fact that DTMF tones are standardized and are uniquely linked to a number (and # or *) on the telephone keypad.
Echo Cancellation Echo cancellation is the process of eliminating echo from voice communication to improve the quality of the call. It is necessary because speech compression techniques and packet processing delays generate echo, of which there are 2 types, acoustic echo and hybrid echo. Echo cancellation improves voice quality in VoIP calls and also reduces the required bandwidth due to silence suppression techniques.
ECM Error Correction Mode Used in conjunction with memory storing fax machines, ECM allows for the receiving fax machine to request retransmission for a page where some errors were detected in the frames of that page. If the receiving fax machine is unable to receive an error free page the fax transmission may fail and the fax connection terminated. On networks with some packet loss, fax transmissions will routinely fail when ECM is enabled because of the low tolerance allowed for any packet loss.
GR-909 Test A standards based suite of electrical tests that have been adapted for the VoIP industry and test for such problems as unwanted voltage on the phone lines, an off hook device keeping the line open, and even when no phone is connected on the line. Some VoIP routers include the GR-909 test in their diagnostic tools.
IAD Integrated Access Device Equipment at the customers location that is used to convert digital signals back to voice. Usually used in association with a DSL connection.
IAX Inter-Asterisk eXchange Protocol, (pronounced "eeks") (now commonly meaning IAX2) is an Asterisk communications protocol for setting up interactive user sessions (both audio and/or video) and supports any type of codec.
IVR Interactive Voice Response An integrated software information system that speaks to callers and uses menus and voice responses. By using touch-tone keypad entries to interact with the software, you get voice responses with real time data.
Jitter As data load increases and decreases, routers on the Internet can create slightly different times that individual packets take to travel from one point to another point. This variation in time is known as jitter.
Latency The time it takes for a packet to reach its destination. Higher delay times can be an issue, especially for VoIP, where voice delay can be recognized with latency higher than 150 milliseconds. Higher than 500 milliseconds and the conversation is going to be very problematic.
LERG Local Exchange Routing Guide Is a database of the first 6 digits of a telephone number, updated on a regular basis, that provides information for routing telephone calls over the Public Switching Telephone Network, as well as, enables identification of what local company the number belongs to.
LNP Local Number Portability is the ability of a US telephone customer to retain their phone number if they switch to another local telephone provider.