Cisco Cisco IP Contact Center Release 4.6.1 Leaflet

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Cisco Unified Contact Center Enterprise 7.5 SRND
Chapter 2      Deployment Models
IPT: Multi-Site with Centralized Call Processing
Best Practices
VoIP WAN connectivity is required for RTP traffic to agent phones at remote sites.
RTP traffic to agent phones at remote sites may require compression to reduce VoIP WAN 
bandwidth usage. It may be desirable for calls within a site to be uncompressed, so transcoding 
might also be required depending upon how the Cisco Unified Communications deployment is 
designed.
Skinny Client Control Protocol (SCCP) or SIP call control traffic from IP phones to the Unified CM 
cluster flows over the WAN.
CTI data to and from the Unified CCE Agent Desktop flows over the WAN. Adequate bandwidth 
and QoS provisioning are critical for these links.
Because there are no voice gateways at the remote sites, customers might be required to dial a 
long-distance number to reach what would normally be a local PSTN phone call if voice gateways 
with trunks were present at the remote site. This situation could be mitigated if the business 
requirements are to dial 1-800 numbers at the central site. An alternative is to offer customers a 
toll-free number to dial, and have those calls all routed to the centralized voice gateway location. 
However, this requires the call center to incur toll-free charges that could be avoided if customers 
had a local PSTN number to dial.
The lack of local voice gateways with local PSTN trunks can also impact access to 911 emergency 
services, and this must be managed via the Unified CM dial plan. In most cases, local trunks are 
configured to dial out locally and for 911 emergency calls.
Unified CM locations-based call admission control failure will result in a routed call being 
disconnected. Therefore, it is important to provision adequate bandwidth to the remote sites. Also, 
an appropriately designed QoS WAN is critical.
IVR: Treatment and Queuing with Unified IP IVR
As in the single-site deployment, all call queuing is done on the Unified IP IVR at a single central site. 
While calls are queuing, no RTP traffic flows over the WAN. If requeuing is required during a transfer 
or reroute on ring-no-answer, the RTP traffic flow during the queue treatment also does not flow over 
the WAN. This reduces the amount of WAN bandwidth required to the remote sites.
IVR: Treatment and Queuing with Unified CVP
In this model, Unified CVP is used in the same way as Unified IP IVR.
Unified CCE: Transfers
Transfers in this scenario are, from the point of view of the contact center, the same as in the single-site 
scenario. Therefore, the same call and message flows will occur as in the single-site model, whether the 
transferring agent is on the same LAN as the target or on a different LAN. The only differences are that 
QoS must be enabled and that appropriate LAN/WAN routing must be established. For details on 
provisioning your WAN with QoS, refer to the latest version of the Cisco Enterprise QoS Solution 
Reference Network Design Guide
, available at 
During consultative transfers where the agent (not the caller) is routed to a Unified IP IVR port for 
queuing treatment, transcoding is required because the Unified IP IVR can generate only G.711 media 
streams.