Bandwidth

How much bandwidth is being used up either between cameras and their 3VR SmartRecorder or between the 3VR and remote client applications

Solution

Bandwidth is defined as a bit rate measure (typically kbit/sec) of available or consumed data communication resources, or simply, the amount of data that can be/is being transferred.

The amount of bandwidth being consumed between a customer’s cameras and their 3VR VIP Appliance is slightly different than the amount of bandwidth consumed between a 3VR VIP Appliance and remote 3VR client applications depending on what the user is doing with the client applications and what video mode the cameras are using.

If a remote user is simply running System Manager without viewing video or changing settings, the bandwidth consumption would be next to 0 kb/sec.  However, if the user is viewing video, the numbers would be almost the same as the numbers between a single stream camera and a 3VR VIP Appliance.  The latter case is typically what a customer will ask about because the bandwidth consumption on their network will actually be noticeable.

From 3VR 7.0, “Smart Throttling” got introduced which automatically throttles the bandwidth according to the needs of the system and the capabilities of the network which should optimize bandwidth usage.

Several factors that affect the amount of bandwidth used are:

• The number of IP cameras connected to the system

• The resolution, frame rate, quality, and video mode (single, dual, or triple stream in 7.0) of each IP camera

 Following are some pre-calculated examples of setups that may be seen in the field (per camera):

Arecont AV1305 (1.3MP) – Default Settings

• Resolution: 1280x1024 (full resolution)

• Frame Rate: 10 fps

• Quality: Medium

• Scene Complexity: Moderate

• Bandwidth for H.264: ~700 kb/sec

• Bandwidth for MJPEG: ~10,000 kb/sec

• Bandwidth for Dual-Stream: ~1.2 MB/sec

Arecont AV2105 (2MP) – Default Settings

• Resolution: 1600x1184 (full resolution)

• Frame Rate: 10 fps

• Quality: Medium

• Scene Complexity: Moderate

• Bandwidth for H.264: ~1000 kb/sec

• Bandwidth for MJPEG: ~15,000 kb/sec

• Bandwidth for Dual-Stream: ~1.8 MB/sec

The above examples can be used as a base estimate and the individual numbers can be scaled according to the customer’s setup. 

Here is a rough graph of approximate bandwidth values for H.264 vs. Motion JPEG (these are just to give an idea of how resolutions, frames per second and video mode relate to bandwidth usage – note that the scale on the x axis is not linear):

Open

Scaling Information:

• The bandwidth usage more or less scales linearly with frame rate and resolution, so if the frame rate or resolution are lower, the bandwidth would drop in about a 1:1 ratio along with it.
  * [These are rough scales and vary depending on different combinations]

• Usage scales with Quality as follows:

  • Switching from Very Low Quality to Low Quality shows ~15-25% increase

  • Switching from Low Quality to Medium Quality shows ~40-50% increase

  • Switching from Medium Quality to High Quality shows ~35-50% increase

  • Switching from High Quality to Very High Quality shows ~15-30% increase

• Usage scales with Scene Complexity as follows:

  • Switching from No Activity to Low Complexity shows ~80-100% increase

  • Switching from Low Complexity to Moderate Complexity shows ~10-15% increase

  • Switching from Moderate Complexity to High Complexity shows ~140-180% increase

  • Switching from High Complexity to Extreme Complexity shows ~150-250% increase