H.323 Adapted to IP Example
A archetypal accomplishing of H.323 goes above the aboriginal LAN ambience of H.323.
Figure 5-2 illustrates a specific appliance of H.323 on an IP internetwork. Notice that
real-time aspects of H.323 await on User Datagram Protocol (UDP). Both the sessionoriented
control procedures and the abstracts media blazon of H.323 use TCP.
Video I/O
Equipment
Audio I/O
Equipment
User Data
Applications
T.120
System
Control and
User Interface
Video Codec
H.261, H.263
Audio
Codec
G.711, G.722,
G.723, G.723.1,
G.728, G.729
System
Control
H.245
Control
Signaling
H.225
Call
Signaling
RAS
Control
H.225
H.225
Layer
RTP
RTCP
TCP
UDP
UDP
IP
H.323 Adapted to IP