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VoIP subscriber gateways
5.3.1
Local conference
In conference mode, pressing ‘flash’ is ignored by initiator. Messages of signaling protocol, received from
the participants and intended to put the initiator side in hold mode, force this participant to leave the
conference. At that, the initiator and the second participant will switch to the ordinary two-party call mode.
The conference terminates, when initiator leaves; in this case, both participants will receive clearback
message. If one of the participants leaves the conference, the initiator and the second participant will switch to
a standard two party call. Flash is processed as described in Sections
5.1
Call transfer
and
5.2 Call Waiting.
Figure below shows an algorithm of '3-way conference' service performed locally by the initiator via SIP
protocol.