Wireless Access

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Access network design for branch, remote, outdoor, and campus locations with HPE Aruba Networking access points and mobility controllers.
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Short Guard Interval - 20MHz

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  • 1.  Short Guard Interval - 20MHz

    Posted Feb 28, 2014 01:15 PM

    I noticed that Short Guard interval for 20Mhz is only applicable to AP-13X/15X.  Is it really not applicable to AP-225?  If so, what is the reasoning?



  • 2.  RE: Short Guard Interval - 20MHz
    Best Answer

    EMPLOYEE
    Posted Feb 28, 2014 02:37 PM

    thecompnerd,

     

    Short guard interval is a standard that is supported by the AP225.  You should be able to see it in a packet capture of the beacon. 

     

     



  • 3.  RE: Short Guard Interval - 20MHz

    Posted Feb 28, 2014 02:46 PM

    Yep, you're right.  Should've tried that first.  I was going by the GUI help.  When you hover over short guard interval in the GUI, it states only the 13X/15X are capable.  Just needs to be updated to include 22X.



  • 4.  RE: Short Guard Interval - 20MHz

    EMPLOYEE
    Posted Feb 28, 2014 02:52 PM

    thecompnerd,

     

    Let me make sure I am looking where you are looking and what version of code you have:  I am running 6.4.x and this is what I see in the HT-SSID-Profile.  Are you running 6.3?  What version and build?

     

    short-guard.png



  • 5.  RE: Short Guard Interval - 20MHz

    Posted Feb 28, 2014 03:05 PM

    6.3.1.2

     

    shortguard.jpg



  • 6.  RE: Short Guard Interval - 20MHz

    EMPLOYEE
    Posted Feb 28, 2014 03:06 PM

    Thank you.  We will take a look at that.

     



  • 7.  RE: Short Guard Interval - 20MHz

    Posted Mar 09, 2014 02:55 PM
    be aware that SGI maps back to the physical dimensions of you environment. if you are in a large spaces where reflections can come back at substantial power and time delay >350 ns then SGI should not be used. for reference radio waves propagate at about 1ft/ns. the system won't break but the radios will try packets that use SGI and they will fail causing un necessary re transmits

    SGI should never be used outdoors and large spaces like gymnasiums that are using APs with standard internal antennas SGI should probably be turned off.


  • 8.  RE: Short Guard Interval - 20MHz

    Posted Mar 21, 2019 02:19 PM

    How to disable SGI for IAP.??



  • 9.  RE: Short Guard Interval - 20MHz

    EMPLOYEE
    Posted Mar 21, 2019 08:34 PM
    Why would you want to do that?


  • 10.  RE: Short Guard Interval - 20MHz

    EMPLOYEE
    Posted Mar 21, 2019 08:34 PM
    Why would you want to do that?


  • 11.  RE: Short Guard Interval - 20MHz

    EMPLOYEE
    Posted Mar 27, 2019 01:13 AM

    Hi possibleyp,

     

    Not sure, if you already found what you are looking for, but here is a description:

     

    https://community.arubanetworks.com/t5/Controller-less-WLANs/How-to-disable-enable-short-preamble-on-IAP/ta-p/273298