Cisco Cisco IPCC Web Option Design Guide

This chapter discusses the concepts, provisioning, and configuration of Cisco Unified Communications 
Manager (Unified CM, formerly Cisco Unified CallManager) clusters when used in a Unified CCE 
environment. Unified CM clusters provide a mechanism for distributing call processing across a 
converged IP network infrastructure to support Cisco Unified Communications, facilitate redundancy, 
and provide feature transparency and scalability.

This chapter covers only the Unified CCE operation with Unified CM clusters and proposes reference 
designs for implementation.

The information in this chapter builds upon the concepts presented in the Cisco Unified Communications 
SRND Based on Cisco Unified Communications Manager, available at 

Some duplication is necessary to clarify concepts relating to Unified CCE as an application supported 
by the Unified CM call processing architecture. However, the foundational concepts are not duplicated 
here, and you should become familiar with them before continuing with this chapter.

This chapter documents general best practices and scalability considerations for sizing the Unified CM 
servers used with your Unified CCE deployments. Within the context of this document, scalability refers 
to Unified CM server and/or cluster capacity when used in the Unified CCE environment. For 
information on sizing and choosing a gateway, refer to the gateway information in the latest version of 
the Cisco Unified Communications SRND Based on Cisco Unified Communications Manager, available 
at 

Before attempting to size a Unified CM cluster for a Unified CCE deployment, you should perform the 
following design tasks:

Determine the different types of call flows.

Determine the required deployment model (single site, centralized, distributed, clustering over the 
WAN, or remote branches within centralized or distributed deployments).

Determine whether CVP or IP IVR will be used for call treatment, self service, and queueing.