Can you see this entry in your log file?

Discussion in 'ASUS N Routers & Adapters' started by reza.kashef, Nov 26, 2012.

  1. reza.kashef

    reza.kashef New Around Here

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    kernel: COEX: downgraded chanspec 0x2d04 to 0x2b02: channel x used by exiting BSSs

    Hi

    As the topic implies, can you see the entry in your log file?
    I cant find it in the FW source code, so if someone knows EXACTLY what this is please inform me!

    Thanks in advance!
     
  2. RMerlin

    RMerlin Part of the Furniture

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    It's the wireless driver simply adapting itself to the presence of other networks causing interference with it. This is just a normal notice, it doesn't indicate any real problem.
     
  3. KevTech

    KevTech Senior Member

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    I believe it is the wireless downgrading from 40 to 20MHz.
     
  4. reza.kashef

    reza.kashef New Around Here

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    Thank you.

    RMerlin: It is the ”adapting” part I’m interested in.

    This has nothing to do with “downgrading” from 40 to 20MHz, neither with changing of the channel in auto mode.

    I have 2 routers operating in the same neighborhood (roughly the same interference), one with FW .220 and the other with .260.
    In the log file for the .220 router I see the entry all the times but never in the one running .260.
     
  5. RMerlin

    RMerlin Part of the Furniture

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    Asus has been experimenting with ways to make the router more stable under high interference environments. They added a new option to manually trigger that behaviour while they look deeper into the root issue - that's what the Enhanced Interference Management option under Wireless -> Professional will toggle how the router react if there's too much radio interference.

    I'm not sure if that downgrade is related to the channel width or to switching to a different channel. If you have your router set to "Auto" for the channel selection, then that might be what you are seeing in the log - a switch to a less crowded channel. Unfortunately, I don't know enough about the lowlevels of the wireless driver itself to know for sure.
     
  6. reza.kashef

    reza.kashef New Around Here

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    Thanks RMerlin

    Yes, I also suspected that this might have something to do with the "Enhanced Interference Management" (wl interferance).

    As I mentioned before the log entry has nothing to do with a channel or bandwidth change, I think that the driver calls the fw about the interference and at the same time logs this.
    I have found the string in an object file but nothing in the fw source.

    Is it right that the "Enhanced Interference Management" option, when enabled sets interference = 4 and when disabled sets it to 0?

    Oh, by the way, do you know if and where the wl interference equivalent value is stored in nvram?
     
    Last edited: Nov 28, 2012
  7. RMerlin

    RMerlin Part of the Furniture

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    The driver is closed source. Fairly sure that this message comes from the wireless driver itself and not from the firmware.

    That's correct.

    The value itself isn't stored in nvram, only the state of that option you mentioned. The nvram setting wl_noisereduction will be set to 0 or 1.
     

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