Conference add controls can be used to place the user, their current call and any calls they have on hold into a conference. When used to start a new conference, the system automatically assigns a conference ID to the call. This is termed ad-hoc (impromptu) conferencing.
If the call on hold is an existing conference, the user and any current call are added to that conference. This can be used to add additional calls to an ad-hoc conference or to a meet-me conference. Conference add can be used to connect two parties together. After creating the conference, the user can drop from the conference and the two incoming calls remain connected.
For R11.0 and higher, the button has additional features:
When pressed during a normal two-party call, that call is turned into a two-party conference call. This then provides access to the phone’s other conference control, such as to add other parties, without interrupting the call.
During an existing conference, pressing the button (on 1400, 1600, 9400, 9500, 9600, and J100 Series phones) provides a menu to enter the number of an additional party to add to the conference without put the conference on hold. The other parties in the conference can hear the call progress and if answered the other party is immediately in the conference.
For further details, see Conferencing.