QWK.Net Web Services

95 percentile accounting, or the "95% rule," is a common way to allocate and bill for bandwidth usage in dedicated hosting. It's also more accurate from a billing standpoint, as it closely models how we actually pay for bandwidth.

In 95% rule accounting, your site's usage level is sampled periodically, usually every five minutes. The outgoing data rate over the last period is sampled and logged. As an example, if 20 megabytes have been transferred in the last five minutes, you would have an average data rate of about 68.3 kilobytes per second.

Once a whole month's usage data is collected, the data is grouped together for analysis. Typical usage will show that at some periods, your site's usage is much higher than at others. The set of samples is ordered by usage rate, and the top 5% are discarded from the set. This has the effect of chopping off temporary peaks so you aren't billed for them.

As an example, let's say that your site usually uses about 100-120 kilobytes per second during the day. Maybe somebody shows your site to his friends at work, however, and as they're all on high-speed connections, your usage suddenly triples for a few moments. Scenarios like this happen all the time. But the 5% chop ensures that you aren't billed for the "peak peak" rate, only for the "average peak."

After the 5% chop, the remaining data is examined for the highest peak left. This is the rate you're billed on. So, for example, if the highest peak left in your sample set is 125, that's what we'll calculate your bill from. 1 megabit per second of constant traffic (about 125 kilobytes per second) equals about 300 gigabytes of usage in a month. So, if your "average peak" was 125 kb/s, or 1 mbit/s, we would translate that to 300GB.

On all plans, we provide additional "headroom" bandwidth for the occasional peaks mentioned above. We do not throttle you to only your plan rate, which could result in significant slowdowns. Throttled "cap" rates are available upon request, however, if you wish to ensure that your site's usage does not exceed a pre-defined level.