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Jul 17th, 2010
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I have CISCO 7.1  integrated with nortel 81c with 4 PRI-QSIG link, I need to know if its enough for 500 users, if there is any tools in cisco to calculate that,

please provide.


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PATRICK GESCHWINDNER Sat, 07/17/2010 - 13:58
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This is calculated using the Erlang formula. Free Erlang calculators are available in the internet. Use Erlang B for the calculation of necessary B-Channels (which is what you need). Callcenter calculators are using the Erlang-C formula. Here is only one of the many examples:

Erlang B: http://www.erlang.com/calculator/erlb/

Erlang C: http://www.kooltoolz.com/ccm.htm?gclid=COOX0Jq586ICFUfX5woddySqhQ



Mohammed Al-Assadi Sat, 07/17/2010 - 14:20
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Hi Patrick,

I think he is asking about normal users not Contact Center.

Erlang calculation for Call Centers.

Erlang B to calculate IVR and trunk ports ( as you know in IPCC you are expection calls more than agents)

Erlang C to calculate the Agents.


paolo bevilacqua Sat, 07/17/2010 - 22:01
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Erlang "calculations" are useless in most cases.

Some users do a lot of calle and some do never calls.

The only working way is to observe real usage of an exisiting trunk.

jontypearce Wed, 11/30/2016 - 06:39
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There is also an Erlang C Calculator in Excel format which could help with your calculations

Erlang C Calculator

This also contains shrinkage calculations so will be more accurate.


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