Introduction - 3Com MSR 50 Series Configuration Manual

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Introduction

H.323 C
ONFIGURATION
When configuring H.323, go to these sections for information you are interested
in:
"Introduction" on page 2355
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"H.323 Architecture" on page 2357
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"H.323 Fundamentals" on page 2358
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"H.323 Gateway Configuration" on page 2360
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"Displaying and Maintaining the H.323 Gateway" on page 2362
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"H.323 Gateway Configuration Example" on page 2363
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"Troubleshooting" on page 2365
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H.323 is an application-layer control protocol for establishing and terminating
multimedia sessions with participants. H.322 can dynamically adjust and modify
session attributes, such as required session bandwidth, media type (voice and
video), encoding/decoding format of media, and support for broadcast.
H.323 uses the Client/Server model to establish calls through communication
between the gateway and gatekeeper.
H.323, packet-based multimedia communications system, is an ITU-T standard
that specifies the components, protocols, and procedures that provide multimedia
communication services over packet networks that does not provide guaranteed
quality of service (QoS), such as IP. It has long been used by traditional carriers and
network device manufacturers in their VoIP solutions. Now, it is one of the
standards for VoIP.
The H.323 stack is implemented at the application layer. The H.323 standard
includes these protocols:
H.225.0 (including Q.931 and RAS protocol) and H.245 for signaling control
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G.711, G.729, G.723.1, and G.723.A for audio codec
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H.261 and H.263 for video codec
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T.120 series (including T.123, T.124, T.125, T.126, T.127, and T.324) for
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multimedia data transmission.
The real-time transport protocol (RTP) provides end-to-end real-time audio and
video delivery services. Its functionality is enhanced through its control protocol,
the RTP control protocol (RTCP). The primary function of RTCP is to provide
feedback on the quality of data distribution, which allows the application system
to accommodate to different network conditions and helps with fault location and