VoIP

VoIP stands for Voice over Internet Protocol. It is the technology that lets phone calls travel as data packets across the internet instead of over the old copper lines that telephones used for a century. Every call placed through VICIdial is a VoIP call, which is what makes a software dialer possible in the first place.

A VoIP call has two main parts working together. The signaling, usually handled by SIP (Session Initiation Protocol), sets up and tears down the call — it is the part that says "ring this number" and "hang up now." The audio itself rides on RTP, a separate stream of small packets carrying the actual voice. Splitting the job this way is why VoIP can be flexible and cheap.

Because the voice is digital, it has to be squeezed for the network using a Codec, which decides how much bandwidth each call eats and how clear it sounds. The packets then travel out through a SIP trunk to your Carrier, who connects the call to the wider phone network. If those packets arrive late or go missing, you hear the problems as choppy audio — see Packet loss for what that looks like.

VoIP became popular for call centers because it untangles the phone system from physical wiring. Adding an agent no longer means running a new copper line to a desk; it means creating another login. Calls can route to anyone with an internet connection, which is how a Remote agent working from home shows up on the same dialer as the people in the office. It is also far cheaper to place high volumes of calls, since you are paying for internet bandwidth and per-minute carrier rates rather than renting dozens of dedicated phone lines.

For a newcomer, the headline is this: VoIP turns voice into internet traffic, so a reliable internet connection matters as much as a good phone. When call quality drops, the cause is almost always somewhere on the network path, not the dialer software itself. You can read about picking a provider in our guide to choosing a SIP carrier.