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This is a question about a possible error in the book. I just wanted to make a new thread just in case it's not an error. :) I didn't see it noted in sticky.

Page 320 Figure: 9.21

Pairwise Cipher Count = 1
Should this be 3. In reading on page 319 (last paragragh), it says it's configured to support CCMP/AES, TKIP/RC4, or WEP-40. With the Group Cipher type 1 being the lowest common at WEP-40.

If this is correct, the Pairwise Cipher List should lists all 3 supported Pairwise Cipher OUIs.

Figure 9.20 on page 319 reflects a similar diagram.

Is this correct or am I reading it wrong?

Thanks,
Kanan S.

Hi Kanan,
You raise a good question. To be honest, I don't know for sure, but your logic makes sense. I remember having a discussion with the authors about this while the book was being written, and I know the network was setup as described on page 319. My guess here is that this beacon also contained a WPA IE (showing WEP and TKIP), which is the Wi-Fi Alliance's vendor-specific information element, modeled after the RSN IE. In either case, I think you are right that the descriptions in the book are somewhat unclear, as it does not show the WEP and TKIP unicast ciphers.

That's what I was thinking. Thanks for the response.

TKIP/CCMP enabled results in Pairwise Cipher Count = 2, only 1 enabled results in Pairwise Cipher Count =1, enabling WEP would not change the pairwise cipher count because the RSN Information element is only dealing with RSNA and WEP does not qualify as a RSNA.

I don?t believe that the capture file matches what is written in the text.

Anyone correct me if I am wrong, wife does it all the time.

I think it?s safe to assume what I posted is incorrect (did not see any way to delete my earlier post). Section 7.3.2.9.1 Cipher Suites states that you can have TKIP/CCMP and WEP included in the RSN Information Element and the Count Field indicates the number of Pairwise Cipher Suites that are contained in the Pairwise Cipher Suite List field. So yep I was incorrect.