Copyright 2010-2015 Obihai Technology, Inc.
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OBi1000 phones support two methods to conference multiple parties: a) local mixing/bridging and b) external
conference bridge. The user interface is slightly different in each case as described below.
Local Mixing/Bridging
After starting a 3-way conference as described earlier, the user can see the two remote parties both in the Connected
State.
The OBi1000 supports up to 4-way conferencing (with 3 remote parties) using the local mixing/bridging method. To add
a third remote party, make a new call to the target party (or answer a new incoming call from another remote party, if
applicable), which automatically places the two connected calls on hold. When the target party rings or answers,
resume the two original conferees (one at a time by highlighting each holding call on screen and applying the
Add to
Conf
soft-key option to it). Eventually you will have a 4-way conference with three calls in the Connected State.
External Conference Bridge
(SIP/SP Only.) When using an external conference bridge, the conference size is not limited by the phone but by the
conference bridge. Check with your conference service provider on the conference size limit. Again you can start a 3-
way conference as described earlier. In this case the phone first sends a new INVITE to the SIP URL of the conference
bridge to request the conference resources. If successful, the conference bridge replies a 2xx response with a Contact
header that includes the context information for other conferees to access the bridge for this conference call. On that
the phone maintains the call with the bridge in the Connected State and sends a REFER to both conferees to refer them
to the Contact as referenced by the conference bridge. The phone user will then notice that only one connected call to
the conference bridge remains on the screen while the two calls with the initial two conferees are removed.
Presumably the two conferees have also connected to the conference bridge on their own.
To add another conferee, make a new call to the target number (or answer a new incoming call from another party, if
applicable), which automatically holds the call to the conference bridge. When the called target rings or answers,
highlight the call with the conference bridge (currently in the Holding State) and select the
Add to Conf
soft-key
option. At that point the call to the conference bridge is resumed while the new remote party is (or will be if it is still
ringing) referred by the phone to the same conference bridge Contact (as soon as it answers) to be added to the
conference bridge. You can continue to add more conferees this way until it reaches the limit set by the conference
bridge.
To enable external conference bridge operation, insert the rule
{cbridge:sp1(conference)}
in
Phone
Settings
::
OutboundCallRoute
and also enable the option
Phone Settings
::
Calling
Features
::
UseExternalConferenceBridge
. It should be noted that the phone assumes that only conferees that are
on the same SP service or using the same ITSP profile as the conference bridge can be referred to the bridge. For
conferees that are referable, the phone keeps them in the conference using local mixing and will be subject to the local
