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Why am I getting worse performance with UDPROS than TCPROS?

asked 2014-04-09 00:50:28 -0500

Javier J. Salmerón García gravatar image

updated 2014-04-09 22:45:55 -0500

I am doing an experiment that consists on transferring JPG compressed stereo pairs from one node to another at 5Hz. I am measuring the message transfer time using two technologies: UDPROS and TCPROS. The frame sizes tested are 320x240 and 640x480.

The point is that the average message transfer times are better when using TCPROS. In the best case UDPROS matches the transfer times obtained with TCPROS (Very rarely UDPROS gets a little better). How is that possible? Am I doing something wrong?

The technology used is 802.11ac WiFi.

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answered 2014-04-10 01:29:50 -0500

I can confirm this observation. I'm not sure, but my explanation is:

  • Image messages are too large for just one UDP package.
  • Some UDP messages are lost.
  • Some images are dropped, because they are not transmitted completely
  • This images used bandwidth, but they are not counted, because they are corrupted
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Asked: 2014-04-09 00:50:28 -0500

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Last updated: Apr 10 '14