Cisco UBE Aperture Alarm Flows
Cisco UBE alarm breeze depends on arrangement cartography and appearance implemented. The following
call-flow scenarios listed will be acclimated to allegorize the concepts about Cisco UBE
that accept been discussed appropriately far:
■ Cisco Unified Communications Manager—Cisco UBE—Cisco Unified
Communications Manager Express
■ Cisco Unified Communications Manager—Cisco UBE with RSVP—Cisco Unified
Communications Manager
■ Cisco Unified Communications Manager—Cisco UBE—SIP Carrier
■ Cisco Unified Communications Manager—Gatekeeper—Cisco UBE—SIP Carrier
■ Cisco Unified Communications Manager—Via-Zone Gatekeeper—Cisco UBE—
Cisco Unified Communications Manager
Figure 9-9 shows a alarm breeze amid a Cisco Unified Communications Manager server
and a Cisco Unified Communications Manager Express router application Cisco UBE.
Cisco Unified Communications Manager Express uses H.450 for optimized alarm transfers
and alarm assiduously after acute hairpinning. Because Cisco Unified Communications
Manager does not abutment H.450, a alteration involving H.323 VoIP access might
lead to suboptimal cartage flows.
Figure 9-9 Cisco UBE Alarm Flows: Cisco UCM to Cisco UCME
Cisco UBE can be acclimated to break H.450 Cisco Unified Communications Manager and
Cisco Unified Communications Manager Express interoperability issues. In this example,
a alarm amid Phone1-1 and Phone2-1 is transferred to Phone3-1. Because Cisco UBE
supports H.450, the consistent cartage breeze will be anon amid the Cisco UBE router
and Cisco Unified Communications Manager 2. After Cisco UBE, the alarm transfer
would be done application hairpinning on Cisco Unified Communications Manager 1.
RSVP-based intercluster CAC can be implemented application Cisco UBE. Figure 9-10 shows
two Cisco Unified Communications Manager clusters commutual by two Cisco UBE
routers. Each Cisco Unified Communications Manager array has an H.323 alarm leg to the
local Cisco UBE local. The two Cisco UBE routers accomplish RSVP-based CAC, and
because RSVP-based CAC requires media flow-through, a alarm amid the two clusters
will breeze through the two Cisco UBE routers. Note that phones still use the Skinny Client
Control Agreement (SCCP) for signaling against a Cisco Unified Communications Manager
server.
Figure 9-11 shows a simple Cisco UBE deployment breadth Cisco UBE is acclimated to translate
a H.323 alarm leg with a Cisco Unified Communications Manager array to a SIP alarm leg
point to a SIP carrier. Because this is a affiliation to an alien VoIP network, media
flow-through is appropriate to adumbrate centralized IP addresses and affected IP interworking
issues, such as alike clandestine IP addresses.
534 Authorized Self-Study Guide: Cisco Voice over IP (CVOICE)
IP
IP
IP
H.225, H.245
No H.450
H.225, H.245
H.450
Cisco Unified
Communications Manager
Express 1
Cisco Unified
Communications Manager
Call is Transferred Without
Hair Pinning
Phone1-1 Calls
Phone2-1
Phone2-1 Transfers
Call to Phone3-1
Phone2-1
3001
Phone1-1
2001
Phone3-1
4001
Cisco Unified
Communications Manager
Express 2
CUBE
1
2
3
Figure 9-10 Cisco UBE Alarm Flows: Cisco UCM to Cisco UCM
Chapter 9: Establishing a Affiliation with an Internet Telephony Service Provider 535
Cisco Unified
Communications
Manager
RSVP
H.225 and
H.245
H.225 and
H.245
Cisco Unified
Communications
Manager
RTP RTP RTP
SCCP SCCP
H.225 and
H.245
IP IP
CUBE CUBE
CUBE=Cisco UBE
Cisco Unified
Communications
Manager
SIP
H.225 and
H.245
RTP RTP
SCCP
IP
CUBE
SIP
Carrier
Figure 9-11 Cisco UBE Alarm Flows: SIP Carrier Interworking
Figure 9-12 shows an H.323 attendant deployment that includes a Cisco UBE integrated
with a attendant and a SIP carrier. Calls from the Cisco Unified Communications
Manager array are baffled via H.225 RAS from the San Jose attendant to the ITSP gatekeeper,
which again routes the alarm to the Cisco UBE router. Cisco UBE again performs
standard agreement interworking, acceptance access from the Cisco Unified
Communications Manager H.323 arrangement to the SIP carrier network.
Figure 9-12 Cisco UBE Alarm Flows: Attendant and SIP Carrier Interworking
Figure 9-13 shows the abstraction of via-zone enabled gatekeepers application Cisco UBE.
536 Authorized Self-Study Guide: Cisco Voice over IP (CVOICE)
SJC Cisco Unified
Communications Manager
408 Zone
H.225 RAS H.225 RAS
SIP
H.225
RAS
H.225
and
H.245
ITSP Zone
SJC GK ITSP GK
GK=Gatekeeper
CUBE=Cisco UBE
CUBE
SIP
Carrier
SJC Cisco Unified
Communications Manager
408 Zone
1, 2, 5 7, 8, 9, 12
10, 11
13
3, 4
6
14, 15
VIA Breadth 857 Zone
BOS Cisco Unified
Communications Manager
SJC GK VIA GK BOS GK
GK=Gatekeeper
CUBE=Cisco UBE
CUBE
Figure 9-13 Cisco UBE Alarm Flows: Cisco UBE and Via-Zone Gatekeeper
Three gatekeepers are deployed:
■ San Jose gatekeeper: This attendant has a distinct breadth alleged 408.
■ Boston gatekeeper: This attendant has a distinct breadth alleged 857.
■ Via-zone gatekeeper: This attendant has a distinct breadth alleged via-zone (VIA).
The San Jose (SJC) Cisco Unified Communications Manager array is registered at the
San Jose gatekeeper; the Boston (BOS) Cisco Unified Communications Manager array is
registered at the Boston gatekeeper; and the Cisco UBE router is registered at the viazone
gatekeeper.
The San Jose attendant will avenue all calls fabricated to the alien 857 breadth to the via-zone
gatekeeper, and the Boston attendant will avenue all calls fabricated to the alien 408 breadth to
the via-zone gatekeeper.
The via-zone gatekeepers will avenue the calls to the alien 408 and 857 zones, but not
directly to the gatekeepers in San Jose and Boston. Instead, the acquisition will be done
using the bounded VIA zone.
The afterward steps, numbered in Figure 9-13, alarm an archetype alarm breeze from the San
Jose Cisco Unified Communications Manager array in breadth 408 on the San Jose gatekeeper
to the Boston Cisco Unified Communications Manager array amid in zone
857 on the Boston gatekeeper:
1. A alarm is placed from the San Jose Cisco Unified Communications Manager to someone
in breadth cipher 857.
2. The San Jose Cisco Unified Communications Manager sends an ARQ to the San Jose
gatekeeper.
3. The San Jose attendant resolves the 857 that belongs to the via-zone gatekeeper
and sends a Location Appeal (LRQ).
4. The VIA attendant receives an LRQ for 857 and resolves the 857 prefix to the
Cisco UBE. The VIA attendant sends a LCF to the San Jose gatekeeper.
5. The San Jose attendant allotment an ACF that specifies the Cisco UBE to the San Jose
Cisco Unified Communications Manager.
6. The San Jose Cisco Unified Communications Manager sends a SETUP bulletin to
the Cisco UBE for the 857 number.
7. The Cisco UBE sends an ARQ to the VIA attendant with the answerCall=true
parameter set to accept the acceptance call.
8. The VIA attendant responds with an ACF to accept the call. From the perspective
of the VIA gatekeeper, the aboriginal alarm leg is established.
Chapter 9: Establishing a Affiliation with an Internet Telephony Service Provider 537
9. The Cisco UBE aperture has a punch associate that specifies that RAS letters should be
sent to the VIA attendant for all prefixes. The Cisco UBE aperture initiates the
process of resending the alarm by sending the ARQ bulletin with answerCall=false to
the VIA attendant for 857.
10. The VIA attendant knows that prefix 857 belongs to the Boston gatekeeper, and
because the antecedent breadth is the via-zone, the VIA attendant sends an LRQ to the
Boston gatekeeper.
11. The Boston attendant sees prefix 857 as a bounded breadth and sends an LCF pointing to
the Boston Cisco Unified Communications Manager.
12. The VIA attendant allotment an ACF to the Cisco UBE that specifies the Boston
Cisco Unified Communications Manager.
13. The Cisco UBE aperture sends a SETUP bulletin to the Boston Cisco Unified
Communications Manager for the 857 call.
14. The Boston Cisco Unified Communications Manager sends an ARQ to the Boston
gatekeeper to appeal acceptance for the call.
15. The Boston attendant sends an ACF with the answerCall=true parameter.