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I’m a distributor of Nortel and I’m looking for a vendor to sell me software so I can do traffic studies in house or better yet a vendor who can do the traffic studies for us.
Drop me a mail, I can do that in very low cost and promote responses.
mailto:sukcom@sina.com
I am professional traffic engineer in telecommunications.
If you like, I can help you in some traffic studies.Im am involved in forecast calculations in a GSM network. We use Erlang B formula to determine the number of channels for a desired blocking probability. What statistical performance indicator is closer to the Erlang B blocking probality?
There might be a ‘blocking rate’ or on other name , depend on which vender.
I would like to remind you , you can not truth Erlang B 100% for a cellular network due to different conditions.
Thank you for your response. At network level, taking all call attempts in consideration and calculating the failure rate of them, we obtain an indicator called Blocking rate. This indicator has the same significance as GOS from Erlang B, if we assume that the customer will not retry after a failed attempt. At cell level, the differences occurs because of handover coming in or out the cell.
Do you have the same understanding of the correlation between GOS – Erlang B and Blocking rate?I agree with your partly.
Failure attemps might be coursed by some reasons, such as lack of traffic resources, lack of signal resources, radio failure, element trouble, etc. We only take lack of resources in to consideration in blocking rate but others.
Erlang B table working well under 5 conditions. A GSM network is not complied all these conditions in cell level.
I do not take handover as the most serious problem.
But if each of your cell only has a few channels, you need correction for your sum up when you figure out your A-interface and capacity of MSC.On the other hand, radio interference will ‘block’ some of your channels even not in use.
Hope this information can help you more or less.
