Cisco Cisco Customer Voice Portal 8.0(1) Design Guide
9-13
Cisco Unified Customer Voice Portal (CVP) 8.x Solution Reference Network Design (SRND)
OL-15989-06
Chapter 9 Network Infrastructure Considerations
QoS Marking
QoS Marking
The Unified CVP Call Server marks only the QoS DSCP for SIP messages. If QoS is needed for Unified
CVP H.323 signaling and data traffic across a WAN, configure network routers for QoS using the IP
address and ports to classify and mark the traffic as recommended in
CVP H.323 signaling and data traffic across a WAN, configure network routers for QoS using the IP
address and ports to classify and mark the traffic as recommended in
Neither the CVP-Data queue nor the Signaling queue is a priority queue as described in Cisco IOS router
terminology. The priority queue is used for voice or other real-time traffic, while call signaling and
Unified CVP traffic are reserved a certain amount of bandwidth based on the call volume.
terminology. The priority queue is used for voice or other real-time traffic, while call signaling and
Unified CVP traffic are reserved a certain amount of bandwidth based on the call volume.
Network Latency
Once proper application bandwidth and QOS policies are in place, another important consideration in a
distributed CVP deployment is that of network latency. With sufficient network bandwidth, the primary
contributor to latency is distance between the VXML gateway and the CallServer/VXML Server.In
distributed CVP deployments, it is important to minimize this latency and to also understand its effect
on solution performance.
distributed CVP deployment is that of network latency. With sufficient network bandwidth, the primary
contributor to latency is distance between the VXML gateway and the CallServer/VXML Server.In
distributed CVP deployments, it is important to minimize this latency and to also understand its effect
on solution performance.
The primary effect of network latency between CVP components is on the end user’s calling experience.
Call signaling latency, either SIP or H.323, between the CVP Call Servers and voice gateways will affect
the call setup time and may add a period of silence during this setup. This includes the initial call setup
and subsequent transfers and/or conferences that are part of the final call flow. VXML application
document download time is also significantly affected by network latency and will have a pronounced
effect on the ultimate caller experience.
Call signaling latency, either SIP or H.323, between the CVP Call Servers and voice gateways will affect
the call setup time and may add a period of silence during this setup. This includes the initial call setup
and subsequent transfers and/or conferences that are part of the final call flow. VXML application
document download time is also significantly affected by network latency and will have a pronounced
effect on the ultimate caller experience.
Table 9-3
Recommended Port Usage and QoS Settings
Component
Port
Queue
PHB
DSCP
Maximum
Latency
Latency
(Round Trip)
Media Server
TCP 80
CVP-Data
AF11
1
1.
The DSCP (or PHB) value for CVP-Data traffic is only a recommendation. You can choose the actual DSCP value used to mark the traffic according to
your preference.
your preference.
10
1 sec
Unified CVP Call Server, H.323 TCP 1720
Call Signaling
CS3
24
200 ms
Unified CVP Call Server, SIP
TCP or UDP 5060
Call Signaling
CS3
24
200 ms
Unified CVP IVR Service
TCP 8000
CVP-Data
AF11
10
1 sec
Unified CVP VXML Server
TCP 7000
CVP-Data
AF11
10
1 sec
Ingress Gateway, H.323
TCP 1720
Call Signaling
CS3
24
200 ms
Ingress Gateway, SIP
TCP or UDP 5060
Call Signaling
CS3
24
200 ms
VoiceXML Gateway, H.323
TCP 1720
Call Signaling
CS3
24
200 ms
VoiceXML Gateway, SIP
TCP or UDP 5060
Call Signaling
CS3
24
200 ms
H.323 Gatekeeper
UDP 1719
Call Signaling
CS3
24
200 ms
SIP Proxy Server
TCP or UDP 5060
Call Signaling
CS3
24
200 ms
MRCP
TCP 554
Call Signaling
CS3
24
200 ms