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Filter for A-MSDU packets

0

To find the percentage of A-MSDU packets in a wireless packet trace using wireshark, which filter should I use from those mentioned below?

A-MDSU packets : wlan_aggregate.a_mdsu.subframe ..... filter 1
A-MSDU packets : wlan.qos.amsdupresent == 1 ..........filter 2

filter 1 shows there are 0% A-MDSU packets in the trace, whereas filter 2 shows there are 3.5% A-MSDU packets in the same trace.What is the difference between A-MDSU and A-MSDU and which filter is the correct filter to obtain the A-MSDU packets?

Also, how to obtain A-MPDU packets in the trace? Is the filter mentioned below correct?
A-MPDU packets : radiotap.present.ampdu

asked 02 Nov '16, 06:51

Harshada%20Kelkar's gravatar image

Harshada Kelkar
21337
accept rate: 0%

edited 02 Nov '16, 11:47


One Answer:

1

Have you seen this question:

https://ask.wireshark.org/questions/53848/how-to-capture-aggregated-packets-a-mpdu-a-msdu-using-wireshark?page=1&focusedAnswerId=54079#54079

I am embarrassed I don't know what an A-MDSU is. Can you provide some context? Maybe I never read that part of the 802.11 specification.

I think you want your option 2: wlan.qos.amsdupresent

To obtain A-MPDU packets, try sniffing on an an 802.11ac network - that should do. I am no expert as far as A-MPDU, but my experience is that not all drivers will populate that field, but that doesn't mean you won't obtain them. The filter might be described as how to present them in Wireshark if that field is populated.

answered 02 Nov '16, 14:35

Bob%20Jones's gravatar image

Bob Jones
1.0k2515
accept rate: 21%

The filter 1 mentions aggregate.a_mdsu so was confused about what a-mdsu is or what that filter does.

However thanks for the help on a-msdu and a-mpdu filters. This does answer my question. Thanks.

(04 Nov '16, 12:29) Harshada Kelkar

Can you accept the answer? Thats how the site works by voting.

(04 Nov '16, 16:07) Bob Jones