Private branch exchange (PBX) and cloud-based PBX systems

Private Branch Exchanges are phone systems—private telephone networks—used in companies and organizations. They offer key capabilities and features for a business to operate. These often include auto attendant, contact center integration, voicemail, call queues, conferencing, and routing.

The two main types of PBX systems are: 
 

• Traditional on‑premises

                     o    Physical hardware installed at the business location
                     o    Higher upfront cost and ongoing maintenance
                     o    Limited flexibility for remote work
                     o    Requires IT expertise to manage and scale

 

• Cloud-based

                     o    Runs over the internet with no on‑site hardware
                     o    Lower cost with subscription-based pricing
                     o    Easily supports remote and mobile workers
                     o    Scales quickly and is maintained by the provider    

The difference between on‑premises and hosted/cloud PBX is infrastructure. An on‑premises PBX relies on physical hardware installed on location and typically uses traditional phone lines. A hosted or cloud PBX runs over the internet using VoIP technology, which reduces hardware needs, supports remote work, and scales easily.

Phone System gives you PBX capabilities, but without the complicated and expensive equipment. It allows you to replace your existing on-premises PBX system with a set of features delivered from Microsoft 365 or Office 365 that is tightly integrated into your cloud experience.

The Microsoft technology for enabling call control and PBX capabilities in the cloud with Microsoft Teams.  

With Mircrosoft Teams Phone System, users can choose Microsoft Teams to place and receive calls, transfer calls, and mute or unmute calls. Phone System users can click a name in their address book, and place Teams calls to that person. To place and receive calls, Phone System users can use their mobile devices, a headset with a laptop or PC, or one of many IP phones that work with Teams. Phone System administrators can manage calling options and settings from the same console used for messaging, collaboration, and so on.

Calls between users in your organization are handled internally within Phone System, and never go to the Public Switched Telephone Network (PSTN). This applies to calls between users in your organization located in different geographical areas, removing long-distance costs on these internal calls.  

Yes. A virtual PBX system gives small businesses the communication capabilities of a much larger organization without the complexity or upfront investment. Teams can manage calls, use features like auto‑attendants, and add or remove users as the business grows, all while keeping costs low.

The future of PRX systems is moving unified communications as a service (UCaaS). Organizations need communication platforms that can integrate voice, video, messaging, and collaboration into a single seamless experience. UCaaS unifies internal and external channels, resulting in more streamlined operations.