IP PBX
An IP PBX is a private branch exchange that sets up and manages phone calls over the Internet Protocol (IP) instead of traditional PBX lines.
An IP PBX handles internal calls, outside lines, transfers and menus using VoIP technology. Where an analog PBX needs a separate cable and card for every extension, an IP PBX lets phones connect over the existing computer network. It can be an appliance or software installed on the business's own server; when the same software runs in a provider's cloud, it is called a cloud PBX. Open-source PBX software is widely used in this space.
How it works
IP phones and softphones register with the PBX using SIP. The PBX routes a call for an extension to the right device and reaches outside lines through a SIP trunk or a gateway that converts analog lines to IP. Voice travels across the network in small packets, so network quality, meaning delay and packet loss, has a direct effect on call quality.
Why it matters
An IP PBX cuts cabling and hardware costs, brings extensions in different offices onto one system and is open to integration with other software. With an on-premises IP PBX, updates, security and redundancy are the job of the business or its maintenance partner; in the cloud model that work moves to the provider. Adding an AI voice agent to an existing IP PBX is usually done over SIP or by having the PBX forward certain calls.
In Speakline
You don't have to remove your IP PBX to try Speakline. You can start by having the PBX forward after-hours or unanswered calls to Speakline, and connect your line directly later. We compare the options in our guide to connecting your business number to an AI assistant.