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Maximum Number Conccurent L2Cap channels in combination with BLE mesh

As far I know BLE mesh uses the 3 advertisement channels for communication without any synchronization mechanisms. When the mesh protocol emits a package it will send the package on all 3 channels and on the listening site the radio continuously switches between these 3 channels. However, if I have a L2Cap running it uses the other data channels with a timed channel hopping mechanism and thus making radio not listening to the 3 advertisement channels in these time slots. If I have one L2Cap running this is still fine, but if I open more and more L2Cap channels at some point it becomes a problem.  Therefore, I would like to know how many L2Cap channels I can safely open before I destroy my mesh communication.

  • I'm afraid that it is dependent on the individual configuration of the mesh network with regards to re-transmissions, the number of L2Cap channels, as well as the on-air time of each individual L2Cap channel, and the frequency of activity of each L2Cap channel. The on-air time of an L2Cap channel is again dependent on payload length and clock accuracy. 

    You will have to find the optimal configurations by calculation or trial-and-error. 

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