The 95/5 method for traffic calculation

Traffic billing based on bandwidth is always based on a previously defined bandwidth, the so-called Committed Data Rate (CDR).

With this method, the incoming and outgoing bandwidth is measured, this happens at intervals of 5 minutes. A measurement is taken every 5 minutes, over the daily 24 hours and usually over a whole month as the billing period. There are a few measurements coming together. 

The service provider now takes all of the measured values ​​and determines the 5% of the highest measured values ​​of bandwidth in the billing period of one month. He deducts this 5% and simply leaves it under the table in favor of the customer. What remains is 95% of the measured values, which are then included in the calculation. 

Alternatively, service providers offer other billing models, e.g. B. according to the value of the maximum bandwidth. Here the highest value of the monthly measurement is taken at 5 minute intervals. As a rule, this method is the most expensive for the customer. 

Another theoretical possibility would be billing based on a calculated average. Here the mean value is simply calculated from all measured values ​​of the 5 minute interval. However, no service provider offers this method because they would have to provide high bandwidths for a fee, which they do not pay for themselves.

The bandwidth used by a connection can vary greatly. There are individual days on which the CDR is significantly exceeded and the burst rate must be fully utilized. The 95% method is ideal for this.

By eliminating the measured maximum 5% bandwidth from the calculation, such “outliers” have no financial significance for the colocation customer.

If the 5% deduction for the measured values ​​is not enough to achieve the booked bandwidth, the actual bandwidth will be recalculated and additional costs will be incurred. If this happens often, it certainly makes more sense to increase the booked CDR.