PBX (Private Branch Exchange)
Short answer: A PBX, or private branch exchange, is a private phone system that routes calls between internal extensions and connects them to outside lines. Modern IP PBXs such as Asterisk, FreePBX and 3CX run as software and reach the phone network through SIP trunks, which is how ZuteSIP numbers connect to them.
A PBX is what gives a business extensions, ring groups, menus and shared outside numbers. The phone numbers themselves come from a provider.
Definition
Originally a switchboard in a company's building, a PBX today is usually software on a server or in the cloud that speaks SIP to both desk phones and providers.
How it works
Extensions register to the PBX. Inbound calls arrive on a trunk for a DID, and dial-plan rules send them to an extension, ring group, queue or IVR. Outbound calls leave through a trunk, with the PBX choosing the caller ID.
How it applies to ZuteSIP
Add each ZuteSIP number to your PBX as a registration trunk using its SIP username and password, server sip.zutesipdialer.com, and G.711 codecs. Setup pages cover Asterisk, FreePBX, 3CX, FusionPBX and VICIdial. PBX features such as voicemail, recording and IVR menus come from the PBX software; they are not part of the ZuteSIP service.
What ZuteSIP provides vs your PBX
| Feature | Provided by |
|---|---|
| Phone numbers and SIP credentials | ZuteSIP |
| Registration trunk to sip.zutesipdialer.com | ZuteSIP |
| Extensions, ring groups and queues | Your PBX |
| Voicemail, recording and IVR menus | Your PBX software |
Related terms
- SIP trunk
- DID
- IVR
- DTMF
Frequently asked questions
Do I need a PBX to use a ZuteSIP number?
No. A PBX is useful for teams; individuals can use a softphone, the web dialer or call forwarding.
Which PBXs are supported?
Any SIP-compliant PBX. Asterisk, FreePBX, 3CX, FusionPBX and VICIdial are named on the site.
Can one PBX use numbers from several countries?
Yes. Each number is a separate trunk registration, so you can mix countries and number types.
Does ZuteSIP host a PBX for me?
No. ZuteSIP supplies numbers and SIP credentials that your own PBX connects to.