Operation Manual – Process Server Configuration
H3C XE 200/2000 IP PBX
Chapter 2 H.323 Overview
2-1
Chapter 2 H.323 Overview
2.1 Introduction to H.323 Protocol
H.323, packet-based multimedia communications system, is a standard that specifies
the components, protocols, and procedures that provide multimedia communication
services over packet networks. 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 protocol suite is specified for LANs that provide non-guaranteed quality of
service (QoS) and is implemented at the application layer. It includes protocols such as
H.225.0, H.245, G.729, G.723.1, G.711, H.261, H.263, and T.120 series. Among them,
G.723.1, G.729, and G.711 are audio codec protocols; H.263 and H.261 are video
codec protocols; H.225.0 and H.245 are system control protocols; and T.120 series are
multimedia data transmission protocols.
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 isolation as well. These two protocols
work together to ensure real-time voice transmission.
H.323 applies to initiate sessions. It sets up and terminates a multimedia session
involving a group of participants, and dynamically adjusts and modifies session
characteristics such as required media type (voice or video), media encoding/decoding
format, and multicast/unicast.
H.323 adopts the Client/Server model and sets up user calls through communication
between gateway and gatekeeper.
2.1.1 Terms
I. H.323 terminal
The H.323 terminals are communication devices of terminal users. They must support
at least one audio coding format in the H.323 protocol suite. They can also optionally
support video coding formats.
II. H.323 gateway
H.323 gateways are responsible for the signaling conversions between different
signaling protocols and the information conversions between different media formats.
Summary of Contents for XE 200/2000 IP
Page 7: ...Basic Configuration ...
Page 42: ...Process Server Configuration ...
Page 82: ...Location Server Configuration ...
Page 182: ...Feature ...
Page 259: ...System Management ...
Page 341: ...IP Performance and Application ...
Page 349: ...Media Server ...
Page 360: ...Call Services ...
Page 507: ...Appendix A ...
Page 511: ...Appendix B ...