Cisco Cisco Unified Contact Center Enterprise 9.0(2) Guía De Diseño

the capacity tool simply interprets any value greater than zero in the CVP ports input fields to mean that 
CVP is being used for treatment or queueing, and the capacity tool will automatically account for the 
H.323 delivery as part of the agent resource consumption. Varying the number of CVP ports has no 
impact on the resource consumption because the only impact to Unified CM is due to the transfer of the 
call to a selected agent.

A second approach to sizing deployments with CVP is to leave the CVP input fields empty and copy the 
number of agents and the per-agent BHCA into the H.323 DS0s input fields. Both approaches will result 
in the same resource consumption.

IVR port BHCA and average handle time are inversely related. In the Unified CCE Resource Calculator, 
you provide the average call treatment time. The Resource Calculator assumes that this call treatment 
time is applied to the beginning of every agent call, therefore the total BHCA rate to your IVR ports for 
call treatment is equal to the total agent BHCA rate. From those inputs, the Resource Calculator 
computes the number of IVR ports required for call treatment and queueing. However, the Cisco 
Unified CM Capacity Tool also expects you to input the BHCA per IVR port. To compute this value, you 
must divide 60 by the sum of the average call treatment time plus the average speed of answer (ASA). 
For example, if your IVR ports provide 45 seconds of call treatment on average and the ASA is 
15 seconds, then the average IVR port handle time per call will be 1 minute and the BHCA per IVR port 
will be 60 (60/1). If you have services that use different call treatment times and different ASAs, then 
you must compute a weighted average.

For the IP IVR Self Service input fields, you can again use the Unified CCE Resource Calculator to 
determine the number of IVR ports for self-service applications. However, the Cisco Unified CM 
Capacity Tool also expects you to input the BHCA per IVR port for self service. To compute this value, 
you must divide 60 by the self-service average call duration. If you have self-service applications that 
have different handling times, then you must compute a weighted average.

This input is the quantity of dialed numbers in your call center that require call center treatment. The 
number of CTI Route Points entered has only minimal impact on Unified CM resource consumption. The 
resource consumption of processing the CTI route points associated with the ICM JTAPI user is included 
in the resource consumption for IPCC agents.    The resource consumption of processing the CTI route 
points associated with the IP IVR JTAPI user is included in the resource consumption for the IP IVR 
ports.

The number of voice gateways has only minimal impact on Unified CM resource consumption, but the 
number of DS0s and the BHCA per DS0 do have a significant impact on resource consumption.

The Unified CCE Resource Calculator determines the number of voice gateway ports required as input 
to the Cisco Unified CM Capacity Tool. However, in order to compute the BHCA per voice gateway port, 
you must divide 60 by the average call duration of calls using the voice gateway ports. The average call 
duration of calls using the voice gateway is a sum of call treatment time, self service application time, 
average queue time, and agent talk time. For example, if the average call has 60 seconds of call treatment 
followed by 120 seconds of self-service followed by 30 seconds of queueing followed by 150 seconds 
of agent talk time, then the average call duration of calls using voice gateway ports is 360 seconds 
(6 minutes). Therefore, the BHCA per voice gateway port would be 10 (60/6). In most call centers, 
computing the average call duration requires computing a weighted average. The online help for the 
Cisco Unified CM Capacity Tool provides an example of a weighted average.