As a rule, providers offer two basic CDN pricing models: pipeline pricing and per-gigabyte payment. How to identify which one is more cost-effective for you? Learn how bandwidth usage and traffic patterns influence the choice.
General Characteristics of Per-Gigabyte Pricing
This is a flexible model that allows using as much bandwidth as you need anytime during billing period. Some CDN providers offer bandwidth packages (for instance, 100Gb, 5 Tb, 50 Tb), while the rest sell it by gigabyte ($0,01 for 1 Gb). This model is appropriate for businesses that use certain amount of bandwidth and face non-occasional request or traffic spikes.
It is beneficial when CDN cost is based on strictly how much is used, not time it is used, or how often requests are made. As a rule, a traffic/request pattern that is not suitable for pipeline pricing works well with per-gigabyte model.
About Pipeline Pricing
This model is appropriate for project with great web presence. Being also called a 95/5 model, it allows delivering certain amount of bandwidth in a second (for example, 1 Gb per second). This limit can be exceeded, but you are likely to pay more in this case. Suggesting, you order a 1 Gbps CDN and transfer exactly 1 Gb per second, you will have 324 TB in a month. Of course, pipeline will be cheaper than paying for 324,000GB by another model, though, it is not always so.
This model is suitable for businesses with steady request rate and rare traffic spikes. Thus, CDN prices are based on bandwidth-per-second number you will not exceed. This system was created to supply businesses with consistent bandwidth and protect them from occasional traffic spikes. The model is called 95/5, because it is allowed to exceed the threshold during 5% of a month (36 hours), while the rest 95% (28.5 days) bandwidth should stay within limits. Bandwidth samples are taken every 5 minutes, which gives us 8,640 samples a month. The highest 432 samples are not counted, while the rest 95% are analyzed. If the highest number does not exceed the limit, you pay what was anticipated. Otherwise, you have to pay much more.
If you manage successfully your bandwidth within the limits, pipeline pricing is effective. Not satisfied with overpaying for a lot of unused resources? This model is still cheaper than paying for every used gigabyte.
Conclusion: pipeline pricing model is perfect for companies that experience stable traffic/request flow, and do not have traffic spikes too often. Vice versa, you can buy CDN with per-gigabyte model if your site faces huge traffic spikes occasionally.