System information

FCD 901 48
Issue R2A, 07.2009
XMP1 Release 5.5 System Description
Analog conference with signalling
Aastra Proprietary Information Page 2-65
channels, its sends an outgoing active a-bit=0 to all other subscribers
connected to the conference. Then the conference is in the calling state.
If a second active a-bit is now detected (one of the subscribers went
off-hook; a-bit=0), the outgoing a-bits of the conference channels are
switched passive by an incoming passive a-bit (traffic state). The outgoing
a-bits of the subscribers participating in the conference call are active and
show that they are in the calling status.
Adding / deleting conference channels in the traffic state
If the conference detects a new channel with an active a-bit, this channel is
involved in the conference and the outgoing a-bit of this channel is switched
active.
As soon as a channel with a passive a-bit is detected in the conference, its
signal is excluded from the conference and the outgoing a-bit is switched
passive.
Terminating the conference
As long as a conference channel includes an active a-bit (from the
subscriber), the conference remains in the traffic state.
If there is only one more active conference channel, its outgoing a-bit (to the
subscriber) is switched passive by the conference circuit. This indicates that
there is no other conference channel participating in the conference. As
soon as the incoming a-bit of the last conference channel becomes passive,
the conference returns to its basic state.