ATL Telecom IP300S - Manual (Page 49)

IP SIP Phone v2 User’s Guide Mar. 2005
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S t a t i o n l o c k e d !
U n l o c k f i r s t .
9.5. Conference
IP SIP Phone supports Ad Hoc 3-way local conference.
The 【Conference】 key on phone set allows the user to set up a conference call with a
number of people. To set up a conference call:
z Call the first person and press the 【Conference】 button to create a conference, on
which time the red LED of 【Conference】 will be on, indicating that the a conference
has been created.
z Call the second person and press the 【Conference】 button to add the second caller to
the conference, on which time the green LED of 【Conference】 would be on,
indicating that a 3-way local conference has been set up. Otherwise the 【Conference】
led will be off if it failed to create a 3-way local conference.
z Repeat until all callers are added to the call. To conference in additional callers, the last
person called with an IP SIP Phone can call an additional person, that new person can
then call someone else, and so on. This is called “daisy-chaining.
z (Optional) To tear down the 3-way local conference, press 【FLASH】to stop voice
mixing and separate them into two independent calls.
Note
: During a conference, an auditable tone will be played regularly from the hosting phone
to notify all parties that a conference is undergoing. The alerting tone is as the same as
the hold-recall tone and the alerting interval is identical to the hold-recall interval set in
“5. Preferences” / “3.Hold recall”.
9.5.1. Heuristics and constraint
IP SIP Phone supports only 3-way local conference, and it takes some heuristics on hosting a
conference:
z Case 1: if you are talking to 【 】 A Channel while pressing 【 】 Conference :
a. 【 】 The red LED of Conference will be on if a conference can be created.
b. IP SIP Phone will switch to another available channel and wait for user dials out. them.
c. After setting up another call successfully, this new call will be added into the
conference automatically if a conference can be hosted.
d. 【 】 Otherwise, the red LED of Conference will flash for a while to indicate a
conference cannot be set up properly. This may due to the fact that both connected
parties demand a low bit-rate compressed voice CODEC, such as G.723.1(A) or
G.729 (A/B), and thus a conference cannot be held between them since the low
bit-rate compressed voice CODEC is shared between them (
IP SIP Phone
equips with
only one hardware low bit-rate G.723/G.729 CODEC).