ISDN BRI features Page 1757 of 1814International ISDN PRI Feature description and administrationThe register signaling part of this feature is supported for ISDN BRI. TheCNI display is not supported.Multifrequency Signaling for Socotel (MFE)Multifrequency Signaling for Socotel (MFE) is similar to R2 MultifrequencyCompelled (MFC) Signaling, but is not compelled in the same way. Insteadof each signal being answered by another signal of some meaning, each signalis answered by a control frequency which indicates to the other end of the callthat 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 theoriginating end, with a backward signal from the terminating end. Eachsignal must be interpreted using the appropriate table. Unlike R2 MFCSignaling, backward and forward signals use the same frequencycombinations. The need for the concept of an incoming or outgoingsender/receiver is replaced by an MFE sender/receiver, which can act in bothdirections during any single call.Pulsed signals, which are used in R2 MFC Signaling to indicate a messagebeing initiated from the CO which normally replies, are no longer necessarywith the new MFE card.The sequence of messages sent to and received from the CO is transparent tothe ISDN BRI terminal.Multiple Appearance Directory NumberMultiple ISDN BRI terminals on the same DSL can have the same DN. AnISDN BRI and a non-ISDN BRI terminal cannot have the same DN.ISDN BRI multiple appearance DN is not allowed across different DSLs andis also not allowed for non-ISDN BRI terminals.Multi-Party OperationsCall JoinThe Call Join feature allows a controlling party to conference-in or transferan active party to a held party. The controlling party can then hang up. Thecontrolling party’s terminal must be equipped with a Conference 3/6 key, andat least one secondary DN or Call Waiting key.
