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New Member

MCS 7835 latest BHCA how many ?How to calculate

IF the MCS server is rated at 50,000 BHCC how do i work out the max number of BHCA supported ?

If someone from Cisco or anywhere can tell me the number of BHCA that would be great

I realise if I had data I could work out utilisation based on how many calls time etc.

At the moment im looking for max number of BHCA for the lates MCS 7835 single processor platform

THE CM SRND 4.0 mentions the Cisco Callmanager capcity tool

Where can I find this guy


Cisco CallManager Capacity Tool

The Cisco CallManager Capacity Tool requires various pieces of information to provide a calculation of the minimum size and type of servers required for a system. The information includes the type and quantity of devices, such as IP phones, gateways, and media resources. For each device type, the capacity tool also requires the average BHCA and the average utilization time. For example, if all IP phones make an average of 5 calls per hour and the average call lasts 3 minutes, then the BHCA is 5 and the utilization is 0.25. (5 calls of 3 minutes each equals 15 minutes per hour on the phone, which is 0.25 of an hour.)

In addition to the device information, the capacity tool also requires information regarding the dial plan, such as route patterns and translation patterns.

When all the details have been entered, the capacity tool will calculate how many primary servers of the desired server type are required as well as the number of clusters if the required capacity exceeds a single cluster.

The capacity tool replaces the previous mechanisms known as device weights, BHCA multipliers, call type multipliers, and dial plan weights.

At this time, the capacity tool is available to all Cisco employees. Please contact your Cisco representative for more information.




Re: MCS 7835 latest BHCA how many ?How to calculate

Hello Allan,

In the tests that we run to come up with these numbers, we don't bother

measuring BHCA, only BHCC.

The current BHCC ratings for the servers are as follows:

7815 - max 25,000 per server, max 50,000 per cluster (two servers)

7825 - max 50,000 per server, max 125,000 per cluster (four servers)

7835 - max 50,000 per server, 125,000 per cluster (four servers)

7845 - max 100,000 per server, 250,000 per cluster (four servers)

The CallManager Capacity Tool is an internal tool used very heavily by

our Systems Engineers when designing/spec'ng out a system for customers.

The tool has never been released for external use, but your SE could

certainly provide it to you and work with you to use it.

Cheers, Dan
New Member

Re: MCS 7835 latest BHCA how many ?How to calculate

Hi ,


Yes I have the local SE getting the information to me.