Cisco Cisco Customer Voice Portal 8.0(1)

As an example of determining the bandwidth consumed by prompts, assume that a call flow
has 50 prompts with an average size of 50 KB (50,000 bytes) each. Also, assume that the refresh
period for the prompts is defined as 15 minutes (900 seconds) on the HTTP media server.

The WAN bandwidth required for prompts in this call flow can be calculated as follows:

1. 50 prompts * 50,000 bytes * 8 bits = 20,000,000 bits

2. 20,000,000 bits / 900 seconds = 22.2 Kbps per branch

H.323 Signaling Bandwidth

Each call that a local site gateway processes requires approximately 6,000 bytes, plus
approximately 1,000 bytes each time the call is transferred to an agent. Thus, each call requires:

The bandwidth required for the WAN link to a remote branch can be calculated as follows:

Gateway Prompt Caching Considerations

When audio prompts are stored on an HTTP media server, proper gateway prompt caching
methods are necessary to optimize both the performance of the gateway and network bandwidth
consumption. Gateway performance decreases by approximately 35-40% if caching is disabled
entirely.

How to Configure Caching on the Gateway

To configure caching on the gateway, do the following:

1. Set the following on the gateway:

–

ivr prompt memory 15000

–

http client cache memory file 500

–

http client cache memory pool 15000

Note: The 'http client cache memory file' represents the largest size prompt file (in Kbytes)
that can be cached. In general, break up customer prompts larger than 500K (about a
minute in length) into smaller, more manageable pieces to facilitate loading and caching.
For example, queue music could be a repetitive loop of a 30 second prompt. Note also
that because the prompts are streamed, the prompt will not be cached unless the whole
prompt is played. Therefore, you must make prompts a manageable size.

2. Synchronize the datetime between the gateway and the HTTP media server.

Configuration and Administration Guide for Cisco Unified Customer Voice Portal Release 8.0(1)