QSIG Overview
QSIG is a alternative of ISDN Q.921 and Q.931 ISDN D-channel signaling for use in devices
such as PBXs or key systems that are alleged Clandestine Integrated-services NetworkeXchange
(PINX). Using QSIG signaling, a router can avenue admission articulation calls from a
PINX above the WAN to a associate router, which can again carriage the signaling and voice
packets to addition PINX. QSIG is acceptable the accepted for PBX interoperability in
Europe and North America.
Cisco UCM nodes that abutment the QSIG protocol, or added equipment, accomplish these
functions:
■ Telecommunications casework aural its own area
■ Telecommunications casework from the accessible ISDN or PSTN
■ Telecommunications casework amid PINXs in a multisite clandestine network
QSIG ensures the capital functions in Q.931 are agitated from bulge to node. QSIG functions
with these two sublayers:
■ QSIG Basal Call: This accepted defines the signaling procedures and agreement for the
purpose of circuit-switched Alarm Control. This accepted is based on Q.931.
232 Authorized Self-Study Guide: Cisco Articulation over IP (CVOICE)
CoderTypeRate=g729r8
CodecBytes=20
cvVoIPCallHistoryIcpif=0
Example 4-16 appearance alarm history articulation Command (continued)
Note See added QSIG Basal Alarm (ECMA-143) advice at: http://www.ecma-international.org/
publications/standards/Ecma-143.htm.
■ QSIG Generic Function: This accepted defines the signaling agreement for the control
of Added Casework and Additional Arrangement Features (ANFs) at the Q reference
point. The accepted enables capabilities above a basal alarm capability.
QSIG Features
QSIG includes these features:
■ Basal call: QSIG basal alarm bureaucracy provides the activating enactment of articulation connections
from an basal PINX (PBX or Cisco UCM) above a clandestine arrangement or
virtual clandestine arrangement (VPN) to addition PINX. You charge use agenda T1 or E1 PRI
trunks to abutment the QSIG protocol.
■ Alarm completion: These alarm achievement casework await on the ability alternative and
reservation affection and accommodate Cisco Alarm Back functionality over QSIG-enabled
trunks:
■ Achievement of Calls to Alive Subscribers (CCBS): Back a calling affair receives
a alive tone, the addition can appeal that the alarm complete back the alive destination
hangs up the buzz and becomes available.
■ Achievement of Calls on No Reply (CCNR): Back a calling affair receives no
answer at the destination, the calling affair can appeal that the alarm complete
after action occurs on the buzz of the alleged party.
■ Alarm diversion: Back alarm aberration by rerouting occurs, the basal PINX
receives a appeal from the receiver of the alarm to alter the alarm to addition user. The
system creates a new alarm amid the artist and the diverted-to user, and an
additional Alarm Detail Record (CDR) gets generated. QSIG aberration supplementary
services accommodate call-forwarding capabilities that are agnate to accustomed Cisco UCM
call-forwarding features:
■ Alarm Forward All (CFA) agreement supports Alarm Forwarding Unconditional
(CFU).
■ Alarm Forward Alive (CFB) agreement supports Alarm Forwarding Alive (CFB).
■ Alarm Forward No Answer (CFNA) agreement supports Alarm Forwarding No
Reply (CFNR).
■ To accommodate affection accuracy with added PBXs in the network, the system
passes advice about a forwarded alarm during the alarm bureaucracy and connection
over QSIG trunks. Buzz displays can present calling name and/or number, original
called name and/or number, and aftermost redirecting name and/or cardinal information
to appearance the destination of the forwarded call.
■ Alarm transfer: Back a user transfers a alarm to addition user, the QSIG identification
service changes the affiliated name and cardinal that displays on the transferred
party phone. Alarm identification restrictions can appulse what displays on the phone.
The alarm alteration added account interacts with the aisle backup affection to
optimize the block access back a alarm transfers to a addition in addition PINX.
Chapter 4: Performing Alarm Signaling over Agenda Articulation Ports 233
Note See added QSIG Generic Function (ECMA-165) advice at
http://www.ecma-international.org/publications/standards/Ecma-165.htm
■ Identification services: Back a alarm alerts and connects to a PINX, identification
services can affectation the addition name and/or ID on a buzz in the absolute PINX,
and likewise, the affiliated affair name and/or ID on a buzz in the originating
PINX. QSIG identification restrictions accredit you to ascendancy the presentation or display
of this advice amid Cisco UCM and the affiliated PINX. Supported
supplementary casework administer on a per-call basis, and presentation settings for call
identification advice are set at both ends of the call.
■ Bulletin cat-and-mouse adumbration service: In a QSIG network, back a PINX has a connected
voice-messaging arrangement that casework users in addition PINX, the messagecenter
PINX can accelerate these Bulletin Cat-and-mouse Indicator (MWI) signals to the other
PINX:
■ MWI Activate: Sends a arresting to actuate MWI on the served user’s buzz after
the voice-messaging arrangement receives a bulletin for that phone.
■ MWI De-activate: Sends a arresting to conciliate the MWI afterwards the user listens to
messages in the associated voice-messaging system.
■ Do not afflict (DND) and Do not afflict override (DNDO): Back a user does not
want to be disturbed, the Clandestine Integrated Casework Arrangement (PISN) can reject
calls. DND and DNDO are declared alone because Supplementary-Services Do
Not Afflict (SS-DND) is a account acclimated by a alleged user, and SS-DNDO is a service
used by a calling user.
■ DND: A added account that enables a served user to account the PISN to
reject any calls, or aloof those associated with a defined basal service, addressed
to the served user’s PISN number. The calling user is accustomed an adapted indication.
Incoming calls are alone as continued as the account is active. The served user’s
outgoing account is unaffected.
■ DNDO: A added account that enables a served user to override SS-DND
at a alleged user (that is, to acquiesce the alarm to advance as if the alleged user had not
activated SS-DND).