Alcatel-Lucent 7302 Information Manual page 353

3 When the phone goes off-hook, the ONT reports the off-hook status using the
H.248 signaling. The voice gateway translates the H.248 signaling into a Signal
message to the Class 5 switch. The Class 5 switch connects the voice call to the
voice gateway. The ONT automatically stops the ringing and allows the voice
data to flow through the bearer path to the voice gateway.
4 When the phone goes on-hook, the ONT reports the on-hook status using the
H.248 signaling. The voice gateway translates the H.248 signaling into a Signal
message to the Class 5 switch.
5 When the Class 5 switch receives the Signal message for on-hook, it sends
Disconnect and channel de-allocation messages to the voice gateway and
disconnects the voice channel. The voice gateway in turn sends the H.248
signaling message to the ONT to tear down the bearer path.
5.3 H.248 softswitch mode
The H.248 softswitch application uses a full set of H.248/Megaco signaling
messages to support voice services. Most call features require some type of signaling
interaction with the softswitch.The softswitch supports features such as caller ID,
call waiting, and 3-way calling. See the appropriate ONT Customer Release Notes for
information about supported softswitches. This mode is not supported for package D
or I-240W-S ONTs.
The ONT performs various functions under the direction of the softswitch.
•
notify the softswitch of off-hook and on-hook events
•
provide dial tone locally
•
collect dialed digits and send the digits to the softswitch
•
play ringback tone and busy tone
•
provide caller ID FSK transmission with data provided by the Softswitch
•
establish or disconnect real-time protocol (RTP) bearer path and RTP control
protocol (RTCP) to another VoIP media gateway
Figure
Alcatel-Lucent 7302 ISAM | 7330 ISAM FTTN | 7360 ISAM FX ONT R04.06.02
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ONT Product Information Guide
5-2 shows the softswitch network topology.
5 — VoIP overview
November 2013 5-7