By Steve Hicks, N5AC
Just a note here to explain for anyone trying to optimize or reduce network bandwidth how much control you have over the bandwidth. The SmartSDR architecture was designed to allow a lot of control over the bandwidth between the client and the server. Here are the components that generate network traffic and the control you have over that traffic:
- The audio codec today has a single setting that we control that provides excellent fidelity -- we really felt that this was the last thing most folks would want to compromise and so for SmartSDR v1.4.0, you don't get to control the bandwidth here. The codec is running at something under 80kbps for receive audio, independent of the number of slices you are running.
- Each panadapter consumes bandwidth based on two factors: the frame rate and the width of the panadapter. The height does not matter. You can reduce the width of the display and you can control the frame rate by adjusting the FPS control on each panadapter. A typical 25FPS fram rate and a 1500 pixel width will generate about 500kpbs of data. Slow the frame rate to 5FPS and the bandwidth will perfectly scale down to 100kbps
- The waterfall works very similarly to the panadapter. With the same 1500 pixel width and a rate of 80, the waterfall will consume about 650kbps. Reduce the rate to a setting of 40 and now the same display will consume only 55kpbs
- Metering today is fixed and will vary based on the number of slices you have (largely) and will consume about 30-60kbps
- The discovery protocol will take about 2kbps
So if you are in a constrained bandwidth situation, altering the speed of your displays will give you a lot of control.