VoIP — Voice over Internet Protocol
What is VoIP?
VoIP (Voice over IP) is the technology that carries voice calls as digital data packets over an internet or private IP network instead of a traditional circuit-switched phone line, using protocols like SIP for call signaling and RTP for the actual audio stream. VoIP is the foundation underneath SIP trunking, cloud phone systems, and most modern business calling — a call still may terminate onto the traditional PSTN at some point, but the leg from a VoIP phone or app travels as IP data.
More detail
VoIP call quality depends on the underlying network's latency, jitter, and packet loss — the same factors that affect any real-time data traffic — which is why a dedicated or well-managed connection generally sounds better than a congested one.
SIP is the most common signaling protocol for setting up and tearing down a VoIP call, while RTP carries the actual voice audio once the call is connected.
Frequently asked
- Is VoIP the same thing as SIP trunking?
- No — VoIP is the broader technology of carrying voice as IP data; SIP trunking is a specific commercial and technical arrangement that uses VoIP (and the SIP protocol) to connect a business phone system to the public network.
- Why does VoIP call quality sometimes vary?
- Because it depends on the underlying IP network's real-time performance — latency, jitter, and packet loss all affect audio quality, which is why VoIP calls can sound different across a congested Wi-Fi connection versus a stable wired one.
See also
Build it on Orbit
Voice, messaging, email, video, and AI agents on one platform and one pay-as-you-go bill. Start free — no credit card required.