Cisco Cisco IPCC Web Option Design Guide

The link should preferably be a dedicated circuit and not be tunneled across the highly available 
(HA) WAN. See 

, at the beginning of the section on 

, for more information on path diversity.

A single link, shown in 

, carries both Unified ICM Central Controller Private traffic and 

VRU/CM PG Private traffic. Single-link implementations are more common and less costly than 
dual-link implementations.

Less costly than separate-link model.

Fewer links to maintain, but more complex.

The link does not have to be redundant. If a redundant link is used, however, latency on failover must 
not exceed 500 ms.

Separate QoS classifications and reserved bandwidth are required for Central Controller 
high-priority and PG high-priority communications. For details, see 

Link sizing and configuration must be examined before any major change to call load, call flow, or 
deployment configuration. This is especially important in the single-link model.

The link should preferably be a dedicated circuit fully isolated from, and not tunneled across, the 
highly available (HA) WAN. See 

, at the beginning of the section on 

, for more information on path diversity.

Clustering over the WAN with Unified CCE System PG is not supported 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 

126029

ICM A

ICM B