Guy Harris <> changed:

           What    |Removed                     |Added
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |NOTABUG

--- Comment #1 from Guy Harris <> ---
Wireshark reports what it sees in the packet: Supported Channels element

The Supported Channels element contains a list of channel subbands (from those
channels defined in in which a STA is capable of operating. The
format of the Supported Channels element is shown in Figure 9-144.

                                  One (first channel, number of
                                  channels) tuple for each subband
         | Element ID |  Length  | First Channel | Number of |
         |            |          |     Number    |  Channels |
 Octets:        1           1             1            1

           Figure 9-144—Supported Channels element format
The Element ID and Length fields are defined in

The First Channel Number field is set to the first channel (as defined in in a subband of supported channels.

The Number of Channels field is set to the number of channels in a subband of
supported channels.

By "contains a list" it presumably means that, after the Element ID (36) and
Length, there's a sequence of one or more pairs of First Channel Number and
Number of Channels.  That's how Wireshark dissects it - it just iterates over
the First Channel Number/Number of Channels pairs.

So whatever sent the packet sent it as:

  0x24    Element ID: 36
  0x0a    Length: 10
  0x24    First Channel Number: 36
  0x04    Number of Channels: 4
  0x34    First Channel Number: 52
  0x04    Number of Channels: 4
  0x64    First Channel Number: 100
  0x0c    Number of Channels: 12
  0x95    First Channel Number: 149
  0x04    Number of Channels: 4
  0xa5    First Channel Number: 165
  0x01    Number of Channels: 1

This means that the channels that the machine that sent the packet supports


so it has 5 ranges of channels in which it can operate, with channel 165 being
in the 5th of those ranges.

The ranges are based solely on a division of the channels into sequences of
contiguous channel numbers; think of it as a form of compression.  The same
value *could* have been sent as 25 individual channel numbers.

The ranges, in this case, happen to be sorted by the lowest channel number, so
that happens to put the one-channel range containing channel 165 into the fifth
range.  That does not, in any way, indicate anything about the regulatory
status of that channel in any locale, so changes to U-NII-3 are irrelevant to
the range in which a given channel appears.

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