Calculating surveillance bandwidth is complex, and inexperienced users can easily underestimate bandwidth, leading to reduced storage durations and/or overloaded networks.
The most common way technicians estimate storage is to use manufacturer or third party calculator tools. However, these tools are too simple for the complex factors impacting bandwidth / storage, a fundamental flaw which fails to reflect real world conditions. In this tutorial, we explain these key issues and give our recommendations for how to most accurately calculate surveillance storage needed.
Most Use Calculators, Despite Issues
Despite their high potential for inaccuracy, most people use calculators. They are simple to use for even novices, typically asking only for a few basics such as number of cameras, resolution, frame rate, with an estimate immediately generated.
From an IPVM member survey, here is the breakdown on preferred method, with a strong majority using storage calculators:
However, it is nearly impossible for calculators to reflect the wide range of conditions in which cameras are installed, as well as the variances between camera models. For example, we asked users how much bandwidth a 1080p H.264 camera uses. Notice how widely bandwidth estimates vary, even using the same resolution, framerate, and CODEC:
All of the respondents could be 'right' even though the answers vary by more than 300%. Differences in cameras used and sites deployed can easily result in massive differences in actual bandwidth/storage consumed. Calculators do not reflect them.