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All right, so let's begin our journey by looking at the structure of an eight to nine 11 match frame.

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So a Mac frame is constructed of common fields and specific fields so quickly provide a short explanation

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of each.

4
00:00:18,210 --> 00:00:22,500
All right, so Mac frames consist of three main structures.

5
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The frame body as a variable length field, it contains information specific to individual frame times.

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FCC stands for frame check sequence.

7
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All right, so it's an error detecting code that's added to each frame.

8
00:00:44,020 --> 00:00:53,440
And in the back header, there's a frame control section, right, so the very first two octets transmitted

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by a station are the frame control.

10
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Protocol version.

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Now, this will provide a version of the 211 protocol used and the values currently zero.

12
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You also have tape in some type.

13
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I'll tell you what the function of the frame actually is, so there are three different frame types

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of field control data management.

15
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There are multiple subtype fields for each frame type, and then each subtype determines the specific

16
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function to perform for its associated frame type.

17
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So to move on.

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To D.C. and from D.C. indicates whether the frame is going into or exiting the distribution system.

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All right.

20
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More frag indicates whether more fragments of the frame are to follow this one.

21
00:01:55,320 --> 00:01:55,860
We're not.

22
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Retry indicates that the frame is being retransmitted.

23
00:02:02,990 --> 00:02:08,660
Power management indicates whether the sending EPA is in active mode or power save mode.

24
00:02:09,550 --> 00:02:15,220
Webb indicates whether or not the encryption and authentication are used in the frame.

25
00:02:16,920 --> 00:02:23,700
Order indicates that the frame is being sent using the strictly ordered service class.

26
00:02:23,940 --> 00:02:26,610
Right now, the field is usually not set.

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Duration ID indicates that time on the channel that the sender is assuming to be occupied from the end

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of the current frame.

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Now, here are some different cases of the fields of addresses, depending on the communication between

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the station and the access point.

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Sequins control is used to recognize frame duplication by setting the sequence number of each frame.