How to calculate network bandwidth and required disk size properly
There are few important factors you should consider during “IP Video System Desing Tool” usage.
- Frame size value calculated by this software is an estimated value.
- In real life IP camrea needs more bandwidth in compare with theoretic value.
FrameSize
When you specify camera resolution and compression level you get just an estimated value of the Frame Size. In real life your camera’s frame size can be twice bigger or smaller.
The frame size depends on
- Image complexity – Frame size can vary from 40% to 230%
- Lens quality – Higher quality – bigger frame size
- Illumination – With low light – smaller frame size
- Noise – more noise – bigger size
To make a more precise calculations you have to make an experiment with your camera in its typical conditions and then put average result in the FrameSize column.
Practical Bandwidth
When you use 100 Mbps(Megabits per second) network it doesn’t mean the network allows 10 streams of 10 Mbps.
Real practical bandwidth value is always smaller.
| Network Type | Practical Bandwidth Value |
| Ethernet 10 Mbps | ~ 7 Mbps |
| Ethernet 100 Mbps | ~ 60 Mbps |
| Ethernet 1000 Mbps | < 500 Mbps |
| WIFI 802.11b 6 Mpbs | ~ 4-5 Mbps |
| WIFI 802.11g 54 Mbps | ~ 13-24 Mbps |
Also some manufacturers of IP cameras , like AXIS recomend to reserve 30% additional bandwidth for future expansion of your video surveillance system.
