Concepts and Glossary

Beginner-friendly explanations of WebRTC, ICE, TURN, STUN, signaling, session tokens, WebSocket, and peer connections.

Concepts and Glossary

This page explains the main terms used in Blendlix Call Service.

WebRTC

WebRTC is a browser and mobile technology for realtime audio, video, and data. Blendlix Call Service uses WebRTC for audio calls.

WebSocket

A WebSocket is a long-lived connection between a client and a server. Blendlix Call Service uses WebSocket to send call events quickly, such as invites, accepts, rejects, and WebRTC messages.

Signaling

Signaling is the process of exchanging setup messages before audio can flow. It includes events such as:

  • call.invite
  • call.accept
  • webrtc.offer
  • webrtc.answer
  • webrtc.ice_candidate

Peer connection

A peer connection is the WebRTC connection between two participants. Once it is connected, audio can flow between them.

ICE

ICE means Interactive Connectivity Establishment. It is the process WebRTC uses to find the best network path between two participants.

STUN

STUN helps a client discover its public network address. This can allow direct peer-to-peer audio when networks permit it.

TURN

TURN relays audio when direct peer-to-peer connection is not possible. TURN is important for users on strict mobile networks, corporate networks, or restrictive routers.

Session token

A session token is a short-lived JWT issued by Blendlix Call Service. The client uses it to connect to the WebSocket endpoint and perform allowed call actions.

Product authentication

Product authentication verifies that a trusted application backend is requesting a call token. Product credentials must stay on the backend.

Context

A context describes why a call exists. Examples can include a task, booking, appointment, support case, delivery, meeting, or any application-defined workflow.