PBX Phone System: What It Is And How It Works

As more advanced and innovative technologies, such as UCaaS (unified communications as a service) and VoIP (voice over internet protocol), have taken their place, the term “PBX” has become obsolete and the form of communication it represents has been mostly obsolete as well.

The private branch exchange (PBX) looks to have been all but forgotten, yet it hasn’t been completely forgotten by corporate executives and owners.

Throughout this article, we will look at the evolution of the PBX to gain a better understanding of its history and different phases.


A private branch exchange, also known as a PBX, is a telephone network that is used by a business or organisation for private communications. It enables its users to communicate both internally (inside their business) and internationally (within the rest of the world) (with customers, partners, and vendors). PBX users can link calls over local lines and call each other on a single external line, which can be used to contact the company. Users within the PBX can connect calls over local lines and call each other on a single external line, which can be used to contact the firm. With this in mind, if you call a company’s mainline and then dial an extension number to speak with someone named “Susan” in the customer service department, you are utilising the company’s private branch exchange (PBX).

To reduce the costs associated with each user having their line to the central office, a PBX is typically implemented. Business phone systems or private telephone networks (PBXs) are used to communicate between employees and customers, and are owned, controlled, and maintained by the organisation rather than by the telephone company.

For a long time, private branch exchanges (PBXs) operated on analogue technology. For long-distance calls over standard phone lines, modern PBXs employ digital technology, which means that digital signals on the local loop are transformed into analogue signals on the long-distance loop. PBXs, on the other hand, can be designed with network switching systems, which allow analogue phones to be used within a digital PBX system. As an alternative to digital systems, it is also feasible to utilise a cloud-based PBX, which is managed fully through the internet rather than through software installed on a server.


The type of PBX equipment required depends on how complex the system is. A typical PBX connected to copper telephone landlines, a hybrid PBX with both analogue and digital connections, an IP-based PBX integrated with voice-over-IP hosted at the facility, or an internet-based PBX are all examples of what is available.

Traditional private branch exchange (PBX) phone systems require landline copper telephone lines, which are connected to a PBX box located on the company’s premises. Generally speaking, a phone switch box is an electronic device that distributes calls to phone lines within the workplace, and those phone lines can link to a limited number of exterior phone lines as well.

An IP PBX, also known as an Internet Protocol PBX, is a telephone system that transmits phone calls using digital telephone signals rather than analogue telephone lines. By connecting phones with Ethernet cables rather than traditional phone lines, there is no need to rewire the entire building. It is also possible for third-party service providers to administer IP PBX solutions. Although hosted systems demand a monthly fee, end-users pay substantially fewer hardware expenditures as a result of their utilisation. Virtual PBXs, often known as mini PBXs, are a less expensive alternative to traditional PBXs that provide fewer features. Their size is appropriate for small businesses.

PBX PHONE SYSTEM (Private Branch Exchange)

The equipment required for the PBX is determined by the complexity of the system and its intended application. There are certain general characteristics, however:

Telephone trunk lines are used to connect two or more telephones. Sitting at the PBX computer, which contains memory for transferring calls into and out of the PBX telephone handset: PBX unified communications router (UCR) with Session Initiation Protocol (SIP), Universal Serial Bus (USB), VoIP, and VoIP gateway network of telephones inside the PBX unified communications router (UCR): There are two types of connections: wired and wireless.
Uninterruptible power supply, wires, and an Internet router telephony application server IP PBX cabinets are all required (UPS)

When a corporation got an incoming call in the olden days, a receptionist would manually connect the call to the right department by using a switchboard and cords to make the connection. It was in the 1960s that the prototypes of PBX were introduced, providing a mechanism for employees to make internal calls within the office or to speak with other people without having to go through the receptionist. In the end, it was a cost-cutting measure that involved improved communication both within and outside of the organisation. By the 1990s, technological breakthroughs in the internet and computer technology had resulted in improvements in telephone networks and infrastructure. In the years following its incorporation into computers, internet access was eventually integrated into telephone networks. PBX systems today include a slew of advanced capabilities, such as voicemail, email notifications for missed calls, extension dialling, call forwarding, call recording, and mobility, among other things.

Last but not least, technology is rapidly changing the way we interact with our telephones. The very seeds sown by PBX systems have developed into something far larger and more in-depth than they were original. Service is known as UCaaS, which stands for “unified communications as a service,” is what we’re talking about here. This communication platform is hosted in the cloud and available through a variety of channels and devices. UCaaS is a cloud-based communication platform that integrates phone service, video conferencing, instant messaging, SMS, fax, and other communication technologies into a single integrated platform.