Definition
H.323 is a standard protocol for video, audio, and data communication (such as telephone and video calls) over the Internet in real time.
It was developed by the International Telecommunication Union (ITU) and encompasses several video and audio communication features, ranging from network administration to call setup.
Functioning of H.323
- H.323 transmits a signal to help two devices find each other on a network if they want to start an audio or video call.
- H.323 applies a signaling protocol (like H.225) to exchange information about the communication’s parameters.
- H.323 uses the RTP to deliver and receive real-time video and audio information.
- When the call is complete, H.323 devices exchange signaling messages to terminate the session successfully.
History of H.323
- Early 1990s: The International Telecommunication Union (ITU) started working on protocols in the early 1990s to enable real-time audio and video communications.
- 1990-2000: The first three versions of the H.323 were released within the first decade of its establishment. Each version improved on the initial versions.
- Recent years: H.323 evolved with subsequent versions enhancing audio and video quality, resolving security concerns and adjusting to changing network environments. However, it started to receive competition from alternative communication protocols like SIP, which became popular in video and voice communication applications.
- Today: H.323 is still used in video conferencing systems, particularly in corporate and government settings. However, it has been replaced by SIP and other modern communication protocols in various contexts like consumer video calling apps and telephony services.