CCIE Voice Lab Blog

6500 - Aggregate Policer Burst Calculation

Sometimes I’ve found it hard to determine certain formulas for Cisco QoS calcuations due to the vast number of documents regarding a certain subset of the large QoS topic.  For the CCIE Voice Lab it is important to understand Cat 6500 QoS.  Within this topic are policers which are made up of either aggregate or microflow.  Part of the aggregate policer configuration is determining the “burst” value.  The best explaination I have found is here.

• Burst = (Rate [bps]) * 0.00025 [sec/interval]) or (maximum packet size [bits]), whichever is greater.

For example, if you want to calculate the minimum burst value needed to sustain a rate of 1 Mbps on an Ethernet network, the rate is defined as 1 Mbps and the maximum Ethernet packet size is 1518 bytes. The equation is:

• Burst = (1,000,000 bps * 0.00025) or (1518 bytes * 8 bits/byte) = 250 or 12144.

The larger result is 12144, which you round to 13 kbps.

DOC URL - Callmanager Ports & Services

Cisco Callmanager > Cisco Unified CallManager Security and Virus Protection Guides > Cisco CallManager TCP and UDP Port Usage > Choose Version

Direct Link found here.

What this is all about….

WELCOME!!!  This blog is intended to be used by myself and anyone else out there who happens to stumble upon the site.  There are numerous other sites which are great for the CCIE Voice lab and I plan to reference them whenever possible.  There will be absolutely NO NDA MATERIAL ALLOWED on this blog for obvious reasons.  I have personally taken the CCIE Voice lab once already and have my next attempt booked for March 2008.  I would like this blog to be a useful tool and encourage anyone who has something beneficial to contribute, to do so.  Thanks for stopping by and good luck to all of you who are on this same journey.