Embedded PRI means that the PRI software resides on the controller. Each Dual Framer MMC is an ISDN interface that will support up to two PRI and/or QSIG links in any mix of protocols. In North America, the link supplies 23 B-channels and 1 D-channel; in Europe, it supplies 30 B-channels and 1 D-channel.
QSIG
T1/E1
Protocols of DMS-100, DMS-250, NI-2 (Bellcore National ISDN, 5ESS, GTD5), IDA-P, Euro ISDN, 4ESS, Euro-ISDN (CTR4)
User/Network Sides
CPN Translations
Fixed and Per-Call Bearer, HLC, NSF, and CLIR
Fractional T1/E1
Fractional PRI
AOC-D and E for ETSI, Italy, Holland
QSIG is a protocol that allows you to connect a minimum of two systems together to form a virtual private network. Because QSIG is an international standard, the virtual private network can benefit corporations that need to connect offices that have systems from different vendors.
QSIG supports both ETSI and ISO protocols. When programming QSIG, you need to know if the system at the other end of the QSIG link is set to either ETSI QSIG or ISO QSIG. For example, if it is running ISO QSIG, then your system must also run ISO QSIG. As well, you need to know if the system at the other end of the QSIG link is set to either QSIG Master or QSIG Slave. For example, if it is set to QSIG Master, then you must set your system to QSIG Slave.
QSIG Calling Name allows the system to send and receive the name of the caller; in turn, the called party will see the name of the caller on the telephone display screen if the appropriate Class of Service options are set. QSIG supports the Calling Name Presentation and Restriction option, which is based on the Calling Line Identification programming.
Incoming calls are diverted to another destination as defined by the user when the service is activated. Activation and deactivation of call forwarding services can be performed by the user or by another authorized user (the current "divert-to" person can deactivate calls from forwarding to them, or they can assign someone else to be the "divert-to" person). System rerouting is also supported across QSIG.
Activation and deactivation correspond to Remote Third Party Forwarding features. Several types of call diversion services are supported:
Call Forward Busy (CFB) - incoming calls to a busy extension are diverted. Activation and deactivation allows others in the network to set and remove forwarding for a particular end-point (for example, voice mail).
Call Deflection (CD) - the user can divert calls to another location by pressing the Forward softkey when notified of a new call (if HCI is implemented this may happen automatically).
Call Forward No Reply (CFNR) - incoming calls are diverted if not answered within a predefined period of time.
Call Forward Unconditional (CFU) - all incoming calls are diverted.
Users can set or cancel message waiting indications on the set of another party to indicate that they wish to be called back or to indicate a voice mail message.
A user can connect two other calls together, of the same basic service, as a new call (there must be three parties). This feature does not support placing a party on soft hold before making an enquiry call to another. This feature maps to the Transfer portion of the MSDN/DPNSS Call Hold and Three-Party Working Service.
Users can offer calls to parties at a busy destination. The busy user receives indication of a call offer, while the calling party receives indication that a call offer has been invoked. The called user has the choice of clearing the current call and being re-rung, putting their current call on hold and accepting the offered call, or ignoring the offered call. The called user will receive the Calling Line Identification and Calling Name Identification of the calling party.
This feature works similarly to DPNSS Call Offer in that the user who offers the call and receives a busy notification may choose to campon or invoke consultation. Immediate campon is invoked if the calling party is transferred to a busy destination until the Campon Recall Timer times out. This feature is not supported when a busy user is reached as a result of diversions that included at least one Call Forward No Reply.
Campon tone security can prevent users from hearing the campon or call waiting tone; therefore, if any party involved in the call has this option enabled, no campon tone is returned. The Class of Service of the calling party controls access to Call Offer. Executive Intrusion is not supported with this feature.
Active calls, connected through the QSIG network, can be replaced with new connections which are more efficient or cost effective (when possible). The originating system requests the path replacement and the terminating system makes the optimized call. None of the existing call path is used when path replacement occurs. There must be an established call (a call that has been answered) before this feature is invoked.
Advice of Charge (AOC) (Europe only) allows a caller to determine the cost of an outgoing toll call. When a caller makes a toll call, the CO establishes the call and sends meter pulses to the system. The system calculates the call charge based on these meter pulses and then displays the charge on the caller's phone display. The system can also be configured to record meter pulses for the caller in the Station Message Detail Records (SMDR).
For more information, refer to Advice of Charge Description.