1 Reply Latest reply on Aug 16, 2017 12:36 PM by cole.hackett

    [Errata] CompTIA Server+ by Troy McMillan

    Behruz Hajeb



      I read the book CompTIA Server+ by Troy McMillan (Exam SK0-004) and found an error and a wrong explanation (or rather incomplete to be more precise).


      The first error that I found is:

      "Page 22, Figure 1.17 Traditional and CNA", the picture states that the "Converged Network Adapter" has Fibre Channel Drivers and Network Card Drivers thus the NIC is usable as a HBA (Host Bus Adapter) for a storage SAN and as a network card for a server. That information is ok, the problem is on Page 41 where the review question 17 asks a question "What type of NIC acts as both a host bus adapter (HBA) for the SAN and also as the network card for the server?".  Possible answers are:

      A. Auto‐MDIX

      B. Full‐duplex

      C. Converged

      D. HBA


      Then on page 445, in the appendix, the answer for the question 17 is D "HBA" which is not correct. The correct answer is C "Converged" as it was stated on page 22 under figure 1.17 Traditional and CNA.


      The second problem is on the page 231 (under chapter 7 Basic Network Security Systems and Protocols). The headline states "Putting It Together". Under the headline the explanation is not complete, and thus provided a confusion for me. After I have referenced several sources on the internet the correct explanation would be as follows:


      - These keys work together to perform both encryption and digital signatures. To provide

      encryption, the data is encrypted with the receiver’s public key, which results in cipher

      text that only the receiver’s private key can decrypt. To digitally sign a document, the

      sender creates what is called a hash value of the data being sent, encrypts that value

      with the sender’s private key, and sends this value along with the message. The receiver

      decrypts the hash using the sender’s public key. The receiver then knows that the hash was sent by the sender since only the sender has the private key which was used to encrypt the hash. Thus making the user who sent the message authentic.


      There are 2 concepts, the first scenario in which the message is encrypted by the sender with receivers public key and then the receiver decrypts the message with his private key which was stated correctly. And the second scenario is signing the document, in which two key pairs are used. The sender first encrypts the hash with his private key, and then the message with the receivers public key, after the message arrives to the receiver, the receiver decrypts the message with receivers private key (his own private key). And after that the hash is decrypted with the senders public key, which is essentially a signature, since only the sender is the one who could have encrypted the message with his specific private key thus making the message authentic.


      I hope I was clear enough. The initial information in the book was not thorough enough, which ended up confusing me and didn't finish the explanation as I expected which in place left me with unanswered questions.