Hi,
Normally, if Marketing provides you some information it is related to billable minutes which means incoming traffic, how to get the total traffic, it is simple: figure out the type of exchange you want to have (Local, Tandem or both), normally when the Tandem exchange is required the billable traffic goes completelly out of the exchange, which will give the total traffic (inbound / outbound traffic), for local switch you have to consider that the billable traffic will be internal (somebody calls it local traffic) and the other part outbound (outside of the exchange), books? well I have not see any due to that I learned about exchanges doing my job: dimensioning exchanges as provider.
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