Nortel Meridian Meridian 1 Feature Description And Administration page 1757

ISDN BRI features Page 1757 of 1814
The register signaling part of this feature is supported for ISDN BRI. The
CNI display is not supported.
Multifrequency Signaling for Socotel (MFE)
Multifrequency Signaling for Socotel (MFE) is similar to R2 Multifrequency
Compelled (MFC) Signaling, but is not compelled in the same way. Instead
of each signal being answered by another signal of some meaning, each signal
is answered by a control frequency which indicates to the other end of the call
that the signal has been received and its transmission can cease. In this way,
signals may originate at either end of the call.
R2 MFC Signaling operates by answering each forward signal from the
originating end, with a backward signal from the terminating end. Each
signal must be interpreted using the appropriate table. Unlike R2 MFC
Signaling, backward and forward signals use the same frequency
combinations. The need for the concept of an incoming or outgoing
sender/receiver is replaced by an MFE sender/receiver, which can act in both
directions during any single call.
Pulsed signals, which are used in R2 MFC Signaling to indicate a message
being initiated from the CO which normally replies, are no longer necessary
with the new MFE card.
The sequence of messages sent to and received from the CO is transparent to
the ISDN BRI terminal.
Multiple Appearance Directory Number
Multiple ISDN BRI terminals on the same DSL can have the same DN. An
ISDN BRI and a non-ISDN BRI terminal cannot have the same DN.
ISDN BRI multiple appearance DN is not allowed across different DSLs and
is also not allowed for non-ISDN BRI terminals.
Multi-Party Operations
Call Join
The Call Join feature allows a controlling party to conference-in or transfer
an active party to a held party. The controlling party can then hang up. The
controlling party's terminal must be equipped with a Conference 3/6 key, and
at least one secondary DN or Call Waiting key.
International ISDN PRI Feature description and administration