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To configure a multicast paging key via Phone interface
1. Press Menu →Feature →Line Key →Line Key2?(e.g.?)
2. Press 
and 
or switch key to select the Multicast Paging in the Type field.
3. Enter the multicast IP address and port number (e.g., 224.5.6.20:2000) in the Value field.
4. The valid multicast IP addresses range from 224.0.0.0 to 239.255.255.255.
5. Press 
or Save soft key to save the configuration
To configure a multicast paging key via Web interface
1. Function Keys→ Line key?
2. Select the desired Key and select Multicast Paging in the Type.
3. Enter the multicast IP address and port number (e.g., 224.5.6.20:2000) in the Value field. The valid multicast IP addresses range from 224.0.0.0 to 239.255.255.255.
4. Click the 
button to save the configuration.
Sending RTP Stream:
Press the multicast paging key when the phone is idle.
The phone sends RTP to a preconfigured multicast address (IP: Port). Any phone in the local network then listens to the RTP on the preconfigured multicast address (IP:Port). For both sending and receiving of the multicast RTP, there is no SIP signaling involved.
The multicast paging key LED illuminates solid green.
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