Thursday, October 21, 2010

Why H.323 is an important Internet protocol?

The H.323 communication protocol is the first complete specification under which the products developed can be used with the transmission protocol widely disseminated (IP). There is much interest and excitement around the H.323 because it appears in the right time. Network administrators have extensive networks already installed and feel comfortable with the IP-based applications such as web access. Moreover, personal computers are becoming more powerful and therefore capable of handling real-time data such as voice and video.

Several independent consulting companies predicted a rapid adoption of H.323. The following chart explains the trend itself

H.323 Components


The H.323 specification defines a generic entity as any component that meets the standard.


One end H.323 is a network component that can send and receive calls. You can generate and / or receive data streams.


An H.323 terminal is one end of the network that provides real-time two-way communications with another H.323 terminal, gateway or multipoint control unit (MCU). This communication consists of control signals, signs, audio, moving color image and / or data between two terminals. According to the specification, an H.323 terminal can provide voice only, voice and data, voice and video, or voice, data and video.


The gatekeeper (GK) is an entity that provides address translation and control access to the network of H.323 terminals, gateways and MCUs. The GK may also offer other services to the terminals, gateways and MCUs such as bandwidth management and locating gateways or gateways.

The Gatekeeper performs two call control functions that preserve the integrity of corporate data network. The first is the translation of addresses of the terminals to the corresponding LAN IP or IPX, as described in the RAS specification. The second is bandwidth management, fixing the number of conferences that may be happening simultaneously in the LAN and rejecting new requests above the level set, so as to ensure sufficient bandwidth for data applications the LAN. The Gatekeeper provides all the above functions for terminals, gateways and MCUs, which are registered within the control zone known as H.323.


An H.323 gateway (GW) is an endpoint that provides real-time two-way communications between H.323 terminals on the IP network and other terminals or gateways in a switched network. In general, the purpose of the gateway is transparently reflect the characteristics of an endpoint in the IP network to another in a switched network and vice versa.

MCU (Multipoint Control Units)

Multipoint Control Unit is designed to hold the conference among three or more points under the H.323 standard, leading the negotiations between terminals to determine common capabilities for processing and controlling audio and video multicasting.

Communication under H.323 provides the audio and video signals. The audio signal is digitized and compressed under one of the supported algorithms such as G.711 or G.723, and the video signal (option) is treated with H.261 or H.263 standard. The data (optional) are handled under the T.120 standard that allows application sharing in conferences point to point and multipoint.

1 comment:

  1. Remarkable! Its genuinely remarkable post, I have got much clear idea on the topic of from this article.


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