Cisco Cisco Customer Voice Portal 8.0(1) Design Guide
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Cisco Unified Customer Voice Portal (CVP) 8.x Solution Reference Network Design (SRND)
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Chapter 4 Designing Unified CVP for High Availability
Unified CVP IVR Service
The survivability.tcl script itself also contains some directions and useful information.
In the event of most downstream failures (including a Call Server failure), the call is default-routed by
the originating gateway. Note that survivability is not applicable in the Unified CVP Standalone and
NIC-routing models because there is no Unified CVP Call Server involved anywhere in those models.
the originating gateway. Note that survivability is not applicable in the Unified CVP Standalone and
NIC-routing models because there is no Unified CVP Call Server involved anywhere in those models.
Additional Cisco IOS Gateway Configuration
The command in the following example disables the TCP timeout for H.225 signaling on the gateway:
voice service voip
h323
no h225 timeout keepalive
This action allows the gateway to lose connectivity with the Call Server or Cisco Unified
Communications Manager but still retain active calls. If you do no t use this command, calls that are still
active that are otherwise unaffected by the failure (that is, the RTP stream is still streaming between the
endpoints) will be disconnected when the TCP session times out.
Communications Manager but still retain active calls. If you do no t use this command, calls that are still
active that are otherwise unaffected by the failure (that is, the RTP stream is still streaming between the
endpoints) will be disconnected when the TCP session times out.
The following commands specify the RTP media timeout:
ip rtcp report interval 2000
gateway
timer receive-rtcp 4
When the gateway detects that RTCP messages have not been received in the specified interval, the call
is disconnected.
is disconnected.
Call Disposition
If the Unified CVP H.323 Service fails, the following conditions apply:
•
Calls in progress
If the Unified CVP H.323 Service fails after the caller has been transferred (transfers include
transfer to an IP phone, VoiceXML gateway, or other egress gateway), then the call continues
normally until a subsequent transfer activity (if applicable) is required from the Unified CVP H.323
Service. If the caller has not hung up and is awaiting further activity, there is a period of 9 to
18 seconds of silence before the caller is default-routed by survivability to an alternate location.
transfer to an IP phone, VoiceXML gateway, or other egress gateway), then the call continues
normally until a subsequent transfer activity (if applicable) is required from the Unified CVP H.323
Service. If the caller has not hung up and is awaiting further activity, there is a period of 9 to
18 seconds of silence before the caller is default-routed by survivability to an alternate location.
If the call has not yet been transferred, the caller hears 9 to 18 seconds of silence before being
default-routed by survivability to an alternate location. (Survivability does not apply in NIC-routing
models.)
default-routed by survivability to an alternate location. (Survivability does not apply in NIC-routing
models.)
•
New calls
New calls are directed by the gatekeeper to an alternate Unified CVP Call Server. If no Call Servers
are available, the call is default-routed to an alternate location by survivability. (Survivability does
not apply in Unified CVP Standalone and NIC-routing models.)
are available, the call is default-routed to an alternate location by survivability. (Survivability does
not apply in Unified CVP Standalone and NIC-routing models.)
Unified CVP IVR Service
With Unified CVP 3.1 and earlier, the IVR Service (previously called the Application Server) was
treated independently of the H.323 Service (previously called the Voice Browser) and VoiceXML
gateways. High availability was achieved by configuring the Unified CVP Voice Browser and VoiceXML
treated independently of the H.323 Service (previously called the Voice Browser) and VoiceXML
gateways. High availability was achieved by configuring the Unified CVP Voice Browser and VoiceXML