IP PBX

How it works

How it works

IP phones and softphones connect to the IP PBX over SIP. For each call, the system checks the dial plan and decides where to send it: by the number dialed, the time of day, or the caller's number. Outside calls go through carriers' SIP trunks.

The system can sit in the company's server room or run in the cloud – then it's a cloud PBX. Both work the same way.

• Extensions, groups, and queues
• Transfer, hold, conference, and voicemail
• IVR (phone menu) and time-of-day routing
• Call recording and call detail records (CDR)

Comparison

IP PBX vs. contact center platform

A PBX connects people: employee to employee, and the company to the outside world. A contact center needs more. It has to route calls by agent skills, show the agent the customer record from the CRM, track service level and handle time, review conversation quality, and run chats in the same queues as calls.

In practice

What to look for

• Open SIP: works with any carrier and any SIP phone
• Capacity measured in simultaneous calls, not just the number of extensions
• CRM connection: via API or through CTI, which links telephony to the agent's computer
• Where it runs: in the cloud or on your own servers

In CONTACT.WORK

How it works in CONTACT.WORK

CONTACT.WORK telephony is built on Asterisk and FreeSWITCH, with Kamailio distributing SIP traffic. Companies use it both as an office PBX and as the core of a contact center, in the cloud or on-premises. You don't have to replace your existing PBX: the platform connects to it over SIP, and with Asterisk it can also work through the API connector. The IVR can read data from your business systems to the caller automatically, such as order status or account balance.