Cisco Cisco IP Contact Center Release 4.6.2 Design Guide

Capacity planning tools for a Cisco Unified Communications deployment include the Cisco Unified 
Communications Sizing Tool and the Cisco Unified Communications Manager Capacity Tool. These 
tools are available at:

Proper login authentication is require. Sizing tools are available for Cisco internal employees and Cisco 
partners.

The Cisco Unified Communications Manager Capacity Tool requires various pieces of information to 
provide a calculation of the minimum size and type of servers required for a Unified CM cluster. The 
focus in this section is on the inputs to the capacity tool that are specific to Cisco Unified CCE.   Details 
on other capacity tool inputs for deployments that are not exclusively for Cisco Unified CCE can be 
found in the Cisco Unified Communications SRND.

The Cisco Unified CM Capacity Tool is available to all Cisco employees and partners at:

The Cisco Unified CM Capacity Tool is currently available only to Cisco employees and Cisco partners.

When all the details have been input, the Cisco Unified CM Capacity Tool calculates how many servers 
of the desired server type are required, as well as the number of clusters if the required capacity exceeds 
a single cluster.

Before using the capacity tool, it is important to review the following facts, guidelines, and 
considerations regarding the contact center input fields.

Agent BHCA and average talk time are inversely related. In the resource calculator, you provide the total 
BHCA for all agents and the agent average call talk time and average after-call work time to determine 
the number of agents required. However, the capacity tool requests the BHCA per agent. To compute this 
value, you must divide 60 (number of minutes in an hour) by the average agent handle time (talk time 
plus after-call work time) measured in minutes. For example, an agent who has an average talk time of 
3 minutes and an after-call work time of 1 minute will have a BHCA of 15 (60/4). Lower BHCA rates 
per agent typically will allow more agents to be supported per cluster.

Many contact centers have different groups of agents with different BHCA rates, talk times, and 
after-call work times. To account for multiple groups of agents with different characteristics, you must 
compute a weighted average. The online help for the Cisco Unified CM Capacity Tool provides an 
example of computing a weighted average.

When contact center calls are treated or queued via CVP and then transferred to a Unified CCE agent, 
the call comes to Unified CM the same as it would from an H.323 gateway. There are two ways to 
account for this resource consumption. One way is to input the approximate number of CVP ports and 
leave the H.323 gateway fields empty. Because the number of CVP ports has no impact on Unified CM, 

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