What is PBX?

PBX or private branch exchange is a telecommunications device used by businesses to route all the calls made within, to, and from their phone network. A PBX connects a business’s internal phone lines to each other and to the PSTN (Public Switched Telephone Network). It has the intelligence to route incoming and outgoing calls based on pre-set rules programmed into it. Each terminating device connected to a PBX is called an “extension” and is assigned a unique (within that network) phone number.

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