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VoIP telephony abbreviations explained

VoIP telephony abbreviations explained


5 min read

Quick Summary

Get to know your DTMF from your DDI when searching for a VoIP provider. Check out some of the more common VoIP terms.

If you're new to the world of VoIP and VoIP providers, the number of terms and acronyms you find yourself coming across can be a bit overwhelming. We've assembled a short list to help you become familiar with some of the more common terms you might discover when looking for a phone system.

VoIP - Voice Over Internet Protocol

VoIP stands for Voice over Internet Protocol. Sometimes known as Voice over IP, it is the method and technology for delivering voice data over the Internet. This is the basis for the VoIP telephony used in offices and homes. Hosted VoIP is a term that is used for VoIP services that are based online in the Cloud.

SIP - Session Initiation Protocol

SIP is an acronym for Session Initiation Protocol. SIP works in conjunction with VoIP and is a communications signalling protocol that creates, modifies and terminates sessions with users. Essentially, SIP is used to start and end VoIP calls and is what establishes the session so you can talk over the Internet.

PBX - Private Branch Exchange

A Private Branch Exchange (PBX) often takes the form of a physical cabinet or box that sits in an office and routes incoming and outgoing calls to different phone extensions. Consumers are now leapfrogging PBX systems in favour of space-saving hosted VoIP Providers which route calls online via the Cloud.

ISDN - Integrated Services Digital Network

ISDN first arrived in 1988 and is an abbreviation of Integrated Services Digital Network. Traditionally this allows the transmission of speech and data over copper telephone wires. An ageing and inflexible system, ISDN is being phased out around the world in favour of the scalability and ease-of-use of VoIP phone systems. BT (British Telecom) has announced that it will be phasing out all UK ISDN lines by 2025.

PSTN - Public Switched Telephone Network

PSTN is a Public Switched Telephone Network and is a term used for the traditional landline. It uses circuit-switched telephony, with physical lines and automated telephone exchanges needed to make phone calls. Again, much like ISDN, this method of telephony requires engineers and installation and is seen as being less flexible than VoIP.

POTS - Plain Old Telephone Service

POTS excitingly refers to the term 'Plain Old Telephone Service' and is a term that is often used in place of PSTN.

DDI - Direct Dial-In

Direct Dial-In or Direct Inward Dialing (DID) as it is sometimes known, enables callers to dial directly through to a specific extension without the need to go through a switchboard operator or receptionist. This feature is often associated with VoIP phones systems which provide separate extensions for individual staff members without the need for additional installation.

DTMF - Dual Tone Multi-Frequency

Dual Tone Multi-Frequency signalling is a telecommunication signalling system which is generated when a telephone touch key is pressed. Each key generates two tones of specific frequencies. DTMF is also referred to as 'touch-tone'. The touch-tone keypad eventually replaced the rotary dial that was used early on in the evolution of the telephone.

IVR - Interactive Voice Response

An IVR or Interactive Voice Response is the automated technology that interacts with callers and allows efficient routing to the appropriate department or member of staff. When making a phone call, callers use touch-tone (DTMF) keypad presses to select pre-programmed options or routes. This technology can be used for a variety of purposes, from making purchases via telephone to checking the weather conditions.

DSL - Digital Subscriber Line

DSL is the acronym for Digital Subscriber Line. It is a collection of technologies typically used in modem or router to transmit data via telephone lines and is the prominent technology for broadband. The typical range for DSL services extends from 256 kbit/s to over 100 Mbit/s.

ADSL - Asymmetric Digital Subscriber Line

ADSL stands for Asymmetric Digital Subscriber Line. It is a type of digital subscriber line (DSL) broadband technology used for connecting to the Internet. It enables fast data transfer over a high bandwidth via telephone lines. ADSL modems accommodate voice data on the same line and provide an 'always on' continuous connection, unlike a regular dialup modem. With ADSL broadband technology, most of the channel is used to transmit downstream to the user with a small proportion given to upstream traffic.

VDSL - Very-high-bit-rate Digital Subscriber Line

Very-high-bit-rate Digital Subscriber Line is also a digital subscriber line but as you may have guessed is even faster than ADSL. The next step in high-speed broadband technology, VDSL systems can use frequencies of up to 30MHz, simultaneously providing data rates over 100 Mbit/s both downstream and upstream.

BYOD - Bring Your Own Device to your VoIP Provider

Bring your own device is a trend that is growing in both the workplace and across schools and colleges too. As the name suggests, this revolves around employees bringing in their own mobile devices or laptops into the office giving them the freedom to work from the comfort of their preferred phone. Because of the flexibility associated with VoIP providers, employees can route business phone numbers and services to their own phones or tablets without any constraints to the way that they work.

Hopefully, this brief summary of commonly associated abbreviations will help you when you are searching for the ideal VoIP service provider for your business. At the very least I hope you now know your DDI and DSL from your DTMF. If you think we've missed any, do give us a call or drop us a line!

VoIP telephony abbreviations explained

Article By

Adrian - Digital Marketing at Yay.com


Digital Marketing at Yay.com

ISO 27001 Business Continuity Accreditation ISO 22301 Business Continuity Accreditation Cyber Essentials Certificate of Assurance G-Cloud accredited by the Crown Commercial Service
ISO 27001 Business Continuity Accreditation ISO 22301 Business Continuity Accreditation Cyber Essentials Certificate of Assurance G-Cloud accredited by the Crown Commercial Service