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Cisco ATA 186 and Cisco ATA 188 Analog Telephone Adaptor Administrator’s Guide (H.323)
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Chapter1 Cisco Analog Telephone Adaptor Overview
H.323 Overview
Figure1-2 CiscoATA 186 as Endpoint in an H.323 Network
Figure1-3 CiscoATA 188 as Endpoint in an H.323 Network
H.323 Overview
H.323 is the International Telecommunication Union (ITU) standard for transmitti ng voice, video, and
data across an IP network. Like other VoIP protocols, the H.323 standard is designed to address the
functions of signaling and session management from within a pac ket telephony network. Signaling
allows call information to be carried across network boundari es. Session management provides the
ability to control the attributes of an end-to-end call. The H.323 standard includes support for call
signaling and control, multimedia transport and control, and bandwidth control for both point-to-point
and point-to-multipoint conferences.
The H.323 standard includes the following protocols:
•Call signaling using the H.225 protocol
•Media control using the H.245 protocol
•G.711, G.722, G.723, G.728, and G.729 audio codecs
•H.261 and H.263 video codecs
•Data sharing using the T.120 protocol
•Real-time transport protocol (RTP) and RTP Control Protocol (RTCP) for media transport
V
Cisco ATA 186
Telephone/fax Ethernet
Broadband CPE
(DSL, cable,
fixed wireless)
Broadband
Layer 3
IP infrastructure PSTN
Voice
gateway
72853
V
H.323 Gatekeeper
V
Cisco ATA 188
Telephone/fax Ethernet
Broadband CPE
(DSL, cable,
fixed wireless)
Broadband
H.323 Gatekeeper
Layer 3
IP infrastructure PSTN
Voice
gateway
72854
V