March 22, 2023

PBX Science

PBX technology, IT information, DIY projects

What is PBX phone system?

What is PBX phone system?


What is PBX phone system? PBX (Private Branch eXchange) is a telecom system/equipment that provide two main tasks:

  • PSTN connection: PBX provide a way to let telephone extensions connect the public switched telephone network (PSTN)
  • PBX provides internal communication, also act a brdige to let extension dial out, or receive imcoming calls.

What is PBX phone system?


How PBX to connect PSTN?

Analog trunk:

After Phone was invented, analog phone line was kept in phone system untill internet technology was introduced into phone system.

Anyalog trunk is a kind of physical exist, because one line of phone trunck (PSTN) depends on two copper wires, which is wrapped by insulation material individually.

Two two wire is also wraped together to form a standard phone cable . Hence, how many PSTN you want to use in your PBX, you have to connect same quantity of phone cables to the PBX.


Digital trunk:

As copper resource is not so rich in earth shell and telecom increased so much in past one hundred year,  the problem people worry was that the Eeath didn’t have enough copper to provide huaman society to produce copper wire for telecom industry.

Afterwards, a big revolution is that optical fiber mostly replace copper wire, which is benefit from digital and internet quick development in the world.

The phone signal was transmitted by analog electrical signal in the past, but now almost all Public Switched Telephone Networks use digital signal via optical fiber.

PBX just needs to connect one optical fiber, which could provide hundreds digital trunks.



What’s IP PBX?

The IPPBX is a telephone exchange system based on the IP protocol. It can transmit voice and video on a local area network or wide area network by dialing an extension.

The biggest advantage is to reduce the cost of communication and the mobility available everywhere.


IPPBX is firstly a PBX (Private Branch eXchange), which can provide voice, video, and instant messaging communications over an IP network.

These communications can be carried out not only on the corporate intranet, but also through the Internet and external networks or even PSTN (Public Switched Telephone Network) telephones.


What is PBX phone system?

VoIP gateways can be combined with traditional PBXs. In addition to providing traditional PBX functions, they can also save long-distance call charges through the Internet, enjoy voice and data services on the same network, and advanced CTI features, or, in pure IP In most cases, it can greatly save investment while providing better mobility and obtaining enhanced redundant security backup. An IPPBX can exist as a hardware entity, or it can be realized by pure software.

IP PBX Functions:

IP PBX could provide huge functions, but depend on hardware and software.

*Unlimited Extensions
* Unlimited Auto Attendants
* Unlimited Voicemail Boxes
* Cell Phone Integration
* Integrated/Overhead Paging (PA System)
* Remote Phones
* Advanced User Interface
* Extension Groups
* Auto Provisioning
* Extension Range Flexibility
* Caller ID Customization
* DID Direct Inward Dialing
* Find Me/Follow Me
* Time of Day Routing
* Extension Call Recording
* On the Fly Recording
* Call Return
* Voicemail Callback
* Voicemail to Email
* SMS Voicemail notification
* Voicemail Web Access
* Voicemail Bypass
* Intuitive VoIP Ready
* Voicemail Blast Groups
* VoIP Ready
* Inbound Call Description
* VoIP Compression
* Outlook Integration
* Announcement Interface
* Call-out
* Call Pickup
* System Diagnositcs
* Multivendor Phone Options
* Analog Phone Support
* BYO Phones
* Call Parking
* Call Barge
* Dial by Name Directory
* Powerful Reporting
* CRM Integration
* Remote Linked Servers
* Operator Console
* Custom Routing Rules
* Conference Rooms
* Outbound Dial Map
* Speed Dial Numbers
* Channel Bank Support
* Multiple Music on Hold
* Analog and Digital T1 Ready
* PSTN or Digital Failover
* NIS Routing
* Advanced Routing (IVR)
* Fast Pass
* Caller Position Notification
* Call Whisper
* Auto call forwarding
* Unified Messaging
* Call Screening
* ANI Routing
* DNIS Routing
* Enhanced Mobility
* Custom VoIP Provider
* Professional Development
* Fax Support
* Fax to Email
* Fax PDF Support
* ACD Features
* Click to Dial
* Softphone
* Call Transfer
* Call Conference
* Live Monitoring