Download Equitel E451 User manual

October 2013 – Ed.1.0
invitation; the ring tone begins to sound and sends a message to the PBX. This message is resent by the PBX
to the telephone that originated the call which in turn emits the tone.
IP network
IP Telephone
192.168.1.25
Ringing...
Ringing...
IP Telephone
192.168.1.99
Switchboard (PBX)
Figure 5. VoIP. Waiting to answer
Step 3: Answer
When receiver picks up the phone, a message indicating that the conversation has been accepted is sent to
the PBX, as well as the necessary data to establish the vocal communication (which codification code is
accepted among the suggested by the emitter; the IP address and the port to which the audio packets must
be sent).
The PBX resends this message to the telephone that began the call.
Figure 6. VoIP. Answer
Step 4: Vocal communication
From this moment on, both telephones begin to exchange the codified audio according the scheme they have
previously agreed.
Figure 7. VoIP. Vocal communication
It is worth to mention that both telephones exchange directly the audio stream, not through the PBX.
EQUITEL E400 Family – Control and communications protocol
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