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Private Branch Exchange System (PBX)

What is Private Branch Exchange System?

A Private Branch Exchange (PBX) is a communication system that plays a vital role in simplifying and strengthening an organisation’s internal and external communications. Essentially, a PBX connects various communication devices, including hubs, switches, telephone adapters, routers, and phone sets. While the size and complexity of PBX systems vary, they range from simple at-home setups upgrading traditional phone lines to sophisticated corporate communication systems owned and operated by individual enterprises.

What does a PBX system do?


A PBX system facilitates the use of multiple phone lines within an organisation, it accomplishes this by dividing a single phone line into private lines identified by extensions, usually assigned 3 or 4-digit numbers. This approach not only simplifies customer access through a single phone number but also enables free internal phone communication. Additionally, PBX systems empower Voice over Internet Protocol (VoIP) communication.

The primary call processing duties of a PBX system 

  1. Establishing connections between the phone sets of two users.
  2. Maintaining connections for the duration required by users.
  3. Disconnecting connections based on user requirements.
  4. Providing information to the organisation for accounting and analytics.

Modern PBX systems offer an array of features, which may vary between systems. Commonly provided features include call management (call blocking, forwarding, logging, transfer, and waiting), streamlined customer experiences (call recording, voicemail, Interactive Voice Response (IVR), and Direct Inward Dialling (DID), and internal communications (conference calls and extensions).

IP-PBX Systems

With the advent of Internet Protocol (IP) telephony (VoIP), PBX systems evolved into IP-PBX. Unlike traditional analog PBX systems, IP-PBX utilises VoIP technology and IP networks to facilitate calls. IP-PBX is feature-rich and does not require separate networks for voice and data communications, offering users access to the internet, VoIP, and traditional phone communications through a single line.

Hosted PBX

Also known as Virtual PBX, a Hosted PBX delivers PBX functionality as a service through the cloud. Companies provide Hosted PBX’s at a monthly cost, requiring users only to have telephone sets and routers. While hosted PBX systems may not cater to complex business needs, they are a cost-effective option as they don’t demand upfront investments and are quick to implement.

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