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  • @Mister Multipath

    >>>>Page 43: Point #8, The mentioned packet (#16) is an ACK, should be any other data packet like #18 for ex.

    >>Actually, you are looking at the wrong capture file. During step #8 you should be looking at >>NON_ENCRYPTED_MSDU.PCAP and packet #16 is indeed a data frame.

    You're right, my bad.

    >>>>Page 47: 10th line from the top, sentence should read: "This transform set is then used in the...".

    >>The sentence is poorly worded. It should read as follows: "This transform set is then used as the confi >>guration settings of the VPN server and client."

    Good, i'll add your sentence as is.

    >>>>Page 59: Q.10, Choice (C), "computers" should be "devices".

    >>Agreed. The question talks about one laptop and an AP. The word "computers" should be replaced with >>"devices"

    Confirmed.

    >>>>Page 85: Point #5, "AES clock cipher" should be "AES block cipher".

    >>What you have not heard about the new clock ciphers? Just kidding. It should be "AES block cipher"

    A gadget to encrypt the time maybe? :)
    Confirmed too.

    >>>>Page 87: On the CCMP Header part of the Figure, "Key IV" should be "Key ID".

    >>Yes and no. There should actually be a little more clarity in the labels in that figure. There are three fields >>in the the CCMP header that are known as the the "Key ID octet" - Those three fields are the Reserved >>field, the ExtIV field and the Key ID field. The ExtIV subfield (bit 5) of the Key ID octet signals that the >>CCMP Header field extends the MPDU header by a total of 8 octets, compared to the 4 octets added to >>the MPDU header when WEP is used. The ExtIV bit (bit 5) is always set to 1 for CCMP.
    >>Bits 6?7 of the Key ID octet are for the Key ID subfield.

    Ok, with reference to Figure 8.15 in section 8.3.3.2 of the 802.11-2007 standard, i can see that there are two "Rsvd" fields, the 1st one is actually missing in the book, and the 1st "Key ID" subfield should be replaced with "Ext IV" so that the whole Key ID octet matches the one in the standard, am i correct?

    >>>>Page 94: Q.7, Shouldn't choice (F) be included?

    >>I believe you are correct. The MSDU priority bit is part of the the MIC calculation and answer F should also >>be a correct answer.

    Confirmed.

    >>We also misspelled in credits the name of Steve Newson who is the the Director, Sales and Systems >>Engineering for Vocera.

    Will add that.
    Confirmed.

    @Dave1234

    >>On page 13, in the last paragraph, it says "The goal of cryptography is to take a piece of information, often >>referred to as plaintext, and, using a process or algorithm, also referred to as a key or cipher....."

    >>I think that could be a bit confusing, as the key and cipher are usually two separate entities.

    >>Also, on page 600, under "key", it says "A process or algorithm used to transform plaintext into encrypted >>text: also referred to as a cipher"

    So, cipher vs. key.. What do you guys think?

    @George Stefanick

    >>In the forward section states, " David Coleman cwne#4 and David Westcott cwne#4"

    A typo, yes.
    Confirmed.

    Thanks for all the feedback and clarifications :)
    Keep 'em coming!

    Regards,
    Mohamed Hany

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