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Administrator Guide for Cisco Unified MeetingPlace H.323/SIP IP Gateway Software Release 5.2.1
OL-6571-02
Chapter 1 Introducing Cisco Unified MeetingPlace H.323/SIP IP Gateway Software Release 5.2.1
Information About Cisco Unified MeetingPlace H.323/SIP IP Gateway Software Release 5.2.1 Components
How H.323 Clients and Cisco SIP IP Phones Communicate by Using Cisco Unified MeetingPlace
H.323/SIP IP Gateway Software Release 5.2.1
H.323 clients and Cisco SIP IP phones—which can be simultaneously deployed—communicate with
Release 5.2.1 and provide another option to join a Cisco Unified MeetingPlace meeting.
The following steps describe how H.323 devices and Cisco SIP IP phones access the Cisco Unified
MeetingPlace Audio Server system by using Release 5.2.1.
Figure 1-2
H.323 Device and Cisco SIP IP Phone Using Cisco Unified MeetingPlace H.323/SIP IP
Gateway Software to Access the Cisco Unified MeetingPlace Audio Server System
.
Step
H.323 Device Description
Cisco SIP IP Phone Description
1.
A caller places a call from an H.323 device
interface.
A caller places a call from a Cisco SIP IP phone.
2.
The H.323 device and Release 5.2.1 communicate
by using H.323.
The Cisco SIP IP phone through Cisco SIP Proxy
Server and Release 5.2.1 communicate by using SIP.
a.
The H.323 device or Cisco SIP IP phone and Release 5.2.1 determine if the Cisco Unified
MeetingPlace Audio Server system can accept the call. By using the Gateway SIM, the
Release 5.2.1 communicates directly with the Cisco Unified MeetingPlace Audio Server system
to determine its availability.
b.
If the Cisco Unified MeetingPlace Audio Server system is unavailable, Release 5.2.1 informs
the H.323 device or Cisco SIP IP phone, and depending upon system configuration, callers may
hear a message informing them that the call cannot be accepted.
c.
If the call is accepted, the H.323 device or Cisco SIP IP phone and Release 5.2.1 negotiate
which codec will carry the voice activity. Release 5.2.1 uses G.711 or G.729a to carry the
encoded speech.
d.
Once codec negotiation is complete, Release 5.2.1 retrieves an IP address and UDP port number
from the Cisco Unified MeetingPlace Audio Server system by using Gateway SIM. This IP
address and UDP port number provide access to the meeting.
IP
IP
H.323 device
Cisco SIP
IP phone
Cisco MeetingPlace
H.323/SIP IP Gateway
Cisco
MeetingPlace
Audio Server
Cisco SIP
proxy server
121556
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2
1
4
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