Jargon-Free Definitions

Telecom Glossary

Clear explanations of the technical terms you'll encounter when preparing for the PSTN switch-off.

Legacy

Public Switched Telephone Network – the traditional analogue phone network using copper wires. Being switched off by January 2027.

Integrated Services Digital Network – a digital phone line technology commonly used for multiple lines and PBX connections. Also being retired.

Wholesale Line Rental – the traditional phone line that broadband and voice services run over. Being discontinued.

Voice over Internet Protocol – technology that allows phone calls to be made over the internet rather than traditional phone lines.

A method of connecting a PBX phone system to the telephone network using internet protocols, replacing ISDN lines.

Private Branch Exchange – a private telephone network within an organisation that manages internal and external calls.

A cloud-based phone system where all infrastructure is managed by a provider, requiring no on-premise hardware.

Microsoft's cloud calling solution that adds phone system capabilities to Microsoft Teams.

Interactive Voice Response – automated phone menus that route callers using voice or keypad input.

An automated system that answers and routes incoming calls based on caller selections.

The process of transferring existing phone numbers from one provider or system to another.

Software application that allows making phone calls from a computer or mobile device.

A desk phone designed to make calls over the internet (VoIP) rather than traditional phone lines.

Analogue Telephone Adapter – a device that connects traditional analogue phones to a VoIP system.

Single Order Generic Ethernet Access – broadband delivered without requiring a traditional phone line (WLR).

Fibre to the Premises – broadband where fibre optic cables run directly to the building, offering the fastest speeds.

Fibre to the Cabinet – broadband where fibre runs to the street cabinet, with the final connection using copper.

A dedicated, private data connection with guaranteed symmetrical bandwidth and SLA-backed performance.

Our team can explain any of these terms in more detail and how they apply to your business.