Video Surveillance Bandwidth And Storage Considerations

bandwidth and storage considerations

Network bandwidth and storage requirements are important considerations when designing a video surveillance system. The factors include the number of cameras, the image resolution used, the compression type and ratio, frame rates and scene complexity.

MPEG-4 calculation

Approx. bit rate / 8(bits in a byte) x 3600s = KB per hour / 1000 = MB per hour
MB per hour x hours of operation per day / 1000 = GB per day
GB per day x requested period of storage = Storage need
Note: The formula does not take into account the amount of motion, which is an important factor that can influence the size of storage required.

Motion JPEG calculation

Image size x frames per second x 3600s = Kilobyte (KB) per hour/1000 = Megabyte (MB) per hour
MB per hour x hours of operation per day / 1000 = Gigabyte (GB) per day
GB per day x requested period of storage = Storage need

bandwidth and storage considerations

Bandwidth and storage calculations

Network video products utilize network bandwidth and storage space based on their configuration. As mentioned earlier, this depends on the following:

  • Number of cameras
  • Whether recording will be continuous or event-based
  • Number of hours per day the camera will be recording
  • Frames per second
  • Image resolution
  • Video compression type: Motion JPEG, MPEG-4, H.264
  • Scenery: Image complexity (e.g. gray wall or a forest), lighting conditions and amount of motion (office environment or crowded train stations)
  • How long data must be stored

Bandwidth needs

In a small surveillance system involving 8 to 10 cameras, a basic 100-megabit (Mbit) network switch can be used without having to consider bandwidth limitations. Most companies can implement a surveillance system of this size using their existing network.

When implementing 10 or more cameras, the network load can be estimated using a few rules of thumb:

  • A camera that is configured to deliver high-quality images at high frame rates will use approx. 2 to 3 Mbit/s of the available network bandwidth.
  • With more than 12 to 15 cameras, consider using a switch with a gigabit backbone. If a gigabit-supporting switch is used, the server that runs the video management software should have a gigabit network adapter installed.

Technologies that enable the management of bandwidth consumption include the use of VLANs on a switched network, Quality of Service and event-based recordings.

 


Use our Video Surveillance Bandwidth and Storage Calculator to get certified solutions that meet your requirements.