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Figure 1: Automotive BroadR-Reach Ethernet HD cameras from two different manufacturers.

Set-up of network, data traffic and timers

The following three video clips show how the system is setup:

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Video clip 1, 2 and 3 (1-2 mins each)

Initial Simulation


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Video clip 4 - run simulation

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A look at the colourful Task Gantt Chart gives you an idea of how much data the system is pushing and the order of it. 

Second simulation - change cameras

There are different ways we can try to solve this problem; The first alternative in trying to avoid dropped frames is to keep the 100 Mbit/s switch port but instead replace the cameras to a "model B" that uses a more efficient compression method (i.e. H.264) with a lower bandwidth requirement. This is done by simply changing the camera (sensor) type to "custom" and choose a previous recorded video data file from a "model B" camera.

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The Task Gannt Chart provides you with the opportunity to drill down and examine the timing behavior.

Third simulation - remove a camera

At least one camera has to be removed in order to avoid too many dropped frames. In addition, one of the remaining cameras might do the job with a lower resolution setting (640*480):

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Video clip 6 - remove one camera, change another to low resolution

There are still a few dropped frames. The results indicate that the limit of the 100 Mbit/s switch capability are reached and we must consider changing to another switch with larger switch port memory buffers.



 The latency distribution has changed significantly: 

Fourth simulation -  introduce 1 Gbit/s

If we need to keep four high resolutions cameras, we have the option to use a bandwidth rate of 1 Gbit/s at switch port 5. The following video shows how to change the original topology to a switch port bandwidth setting of 1 Gbit/s. 
(Note: This shows the advantage of simulation of not yet released or available real world physical hardware. 1000BASE-T1 technology is not yet available, or at least hard to get hold of.)

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Video clip 7 - change switch port settings

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