• That all sounds right, but when you said
    [quote]However, if the value of the first octet is 201 or greater, we now shift to the meaning of ?Regulatory Extension Identifier/Regulatory Class/Coverage Class?[/quote]

    Are we talking about the octet that is immediately after the length? (in this example 55h). If so, are you saying that if that octet was hex C9 or higher (decimal 201), then we wouldn't be talking about a country rule, but the other meanings would take effect? If so, what then happens with the next two octets, 53 and 20?

  • It's actually an "either/or" situation.

    Either ( after ID, Length, Country String ) you have "First Channel etc" ( less than 201 )


    You have "Regulatory Extension Identifier" etc

    In your trace, we have the case of "First Channel etc". In other words, the data included in the octet of "01" hex is 1 decimal, which is less than 200. The receiver's software looks at that value and says "OK, this value is less than 201 decimal, I'm going to interpret everything that comes after the end of the Country String as First Channel, Number of Channels, Maximum Transmit Power Level"

    If the octet had contained ( say ) 201, then it would say to itself "Ah, this value is now equal to or greater than 201 ( equal to in this case ), I'm going to interpret everything that comes after this as Regulatory Extension Identifier, Regulatory Class, Coverage Class"

    If someone can send in a trace that shows "Regulatory" info, that would be great.


  • I understand the concept of its value determining the meanings, just wasn't clear which octet in particular. You say it's the octet that is '01' in the example? I was thinking the '55' octet (in our example). Now we know.

  • Yes, it's always the first one after the Country Strings. What is not well explained in the docs is that after the Regulatory Class/Coverage info ( if present ), you can still have First Channel Number etc, but refering to the particular subset of info under the Channel Set of the Regulatory Class.

    I called someone at the IEEE today to have a chat and they told me some "wonderful" news......all that terminology will be changed in the near future.......I can't wait.

    To add to the joy, I had a peek at the next maintenance release of IEEE-802.11.....

    It's gone from 1233 pages to 2910 pages.

    It's the gift that keeps on giving....

    Just noticed something.....all the sections have been renumbered in the new release......awesome.......


  • Why this stuff is important:


  • Thank you very much
    Your knowledge is very deep, so does your eager to explore, understand and know more

    What if a STA/AP sent a COUNTRY ELEMENT with the value of the first octet less then 201
    so i can't tell their operating class (which is not regulatory domain)?
    How will my STA know whats the sender operating class?
    shell i send this info for every operating class which contain this channel? or is there another way to get this information?

  • Kashani,

    Not only is Daves knowledge deep, his search methodology is amazing.

    He finds, and gives the links to, things I never would have found.

    Thanks again Dave.

  • Tks Guys

    When the value of the first octet after the Country String octets is less than 201, you only have "First Channel/Number of Channels/Maximum Transmit Power Level" and you do not have any "Regulatory Extension Identifer/Regulatory Class/Coverage Class" information, and so you do not need to worry about it in that case.

    Coverage Class gives useful information on timing issues due to propagation delay in outdoor environments, by the way.

    However, if we have the first octet after the Country String equal to or greater than 201 ( it's actually only 201 at present, but that may change in the future ), then you have "Regulatory Extension Identifer/Regulatory Class/Coverage Class" information.

    You would need to code to look at the first octet, then have a decision filter to say "Hey, if this value is less than 201, I need to go to a sub-routine that processes everything from that octet on as "First Channel number etc". If it is equal to or greater than 201, I need to go to a subroutine that processes everything from that octet on as "Regulatory Extension Identifier etc".

    It's an either/or situation.

    In Japan, there is even a metropolitan area where the regulations are different in one physical part of that area from another !!


  • [quote]In Australia the authority is Australian Communications and Media Authority (ACMA). (This ACMA not to be confused with Aruba's ACMA certification)

    Trying to get the technical info required from the website is a nightmare though.

    To be honest, Australia generally tends to just copy other countries like US or Europe, although we don't have a big problem from neighbouring countries, given that it's an island :) [/quote]

    Australia followed the lead of other country's when it comes to UNII-2e by allowing its use (minus those primary radar frequencies and therefore minus 2 channels) but despite this occurring several years ago, hardware manufacturers still don't seem to allow its use in the Australian regulatory domain. Frustrating with the forth-coming 802.11ac... we need those god damn extra 9 channels!

  • Thank you all guys!
    I appreciate your kindness and help.

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