Cisco Cisco Unified Contact Center Enterprise 8.5(1) Prospecto

Carrier call routing must be able to route calls to the alternate site in the case of a site or gateway 
loss. Pre-routing may be used to balance the load, but it will not be able to prevent calls from being 
routed to a failed central site. Pre-routing is not recommended.

Clustering over the WAN with Unified CCE System PG is now supported. However, due to the fact that 
a single Unified CCE System peripheral is controlling all of the Unified IP IVRs and the Unified CM, 
the load-balancing of calls between Unified IP IVRs does not take into account which site the call came 
into; it simply distributes the calls to whichever Unified IP IVR is least loaded. This means that calls 
coming into Site A might be treated by a Unified IP IVR in Site B. Additionally, both the A-side and 
B-side Unified CCE System PG know about all of the Unified IP IVRs. PIM activation logic will 
determine if the A-side or the B-side PIM will connect to each of the Unified IP IVRs. This means that 
the PG at site A might connect to the Unified IP IVR at site B. This means traffic that might not be sent 
optimally over the WAN. In this model, care should be taken to make sure the WAN is sized for proper 
operation given this fact.

In this model, the voice gateways are VoiceXML gateways located in the central sites. Unified CVP is 
centrally located and used for treatment and queuing. 

 illustrates this model.

ICCS

ICM Public

ICM Private

1

2

3

143992

ICM

A

4

5

ICM

B