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802.11ad Decoding Error

0

I have the following snapshot for a capture for 802.11ad DMG Access Point generated by ns3 simulator:

Wireshark Snapshot

While going through the fields of the DMG Beacon, the wire-shark interprets part of the information in a wrong way. For example in the fixed parameter Sector Sweep field (3 Bytes), I pass the following information in the DMG Beacon during my simulation:

  1. Sector Sweep Direction = 0 (Beamforming Initiator)
  2. Sector Sweep CDOWN = 8
  3. Sector Sweep Sector ID = 1
  4. Sector Sweep DMG Antenna ID = 1
  5. Sector Sweep RXSS Length = 0

As a result, the encoding of this information according to the standard as illustrated in the following figure should be as following:

alt text

Byte (0) Byte (1) Byte (2)

00010000 00000100 00000001

In more details:

  1. Sector Sweep Direction = 0 (Beamforming Initiator)
  2. Sector Sweep CDOWN = 00 0001 000
  3. Sector Sweep Sector ID = 0000 01
  4. Sector Sweep DMG Antenna ID = 01
  5. Sector Sweep RXSS Length = 0000 00

Note: The left most bit is the most significant bit.

So as you can see the wireshark dissector interprets them i the opposite way.

asked 04 Aug '15, 09:35

Hany%20Assasa's gravatar image

Hany Assasa
21101114
accept rate: 0%

Wireshark version?

(04 Aug '15, 09:50) grahamb ♦

I am running Wireshark (1.12.6) on Linux @grahamb

(04 Aug '15, 10:25) Hany Assasa

2 Answers:

1

Bug 11419 was filed, and it is now fixed.

answered 05 Aug '15, 19:16

Guy%20Harris's gravatar image

Guy Harris ♦♦
17.4k335196
accept rate: 19%

0

Bugs should be reported via the Wireshark Bug Database. Include as much info as possible (like here), and at least a capture file of the relevant traffic.

answered 05 Aug '15, 00:14

Jaap's gravatar image

Jaap ♦
11.7k16101
accept rate: 14%