Quiz Two study guide/main topics - Thursday, March 13th, 2014...

 1. Hamming codeword.  One question.  Just like on our first quiz.

 2. TIC - Tiny Imaginary Computer show the PC (IAR), ACC (accumulator),
          OUT (Output), and changing values in memory locations that
          are holding data.

          You will be given the operation codes.

          One question.  This TIC program is likely to involve a LOOP.
          Our first quiz did NOT involve any loop, so no Branch 
          statements.  It did NOT execute any statement more than once.

 3. CRC = Cyclic Redundancy Check 

          http://www.cs.uni.edu/~jacobson/023/CRC/ 

          One question.  Just like we practiced in class.

 4. Encryption and decryption, plaintext and ciphertext, Caesar
          substitution and the secret key.  

          No vigenere encrypt or decrypt, only Caesar encrypt and decrypt.

 5. Basics of subnet masks for a class B network, octets, 
                class A, B and C networks and IP numbers.

          Class A: w specifies the network, x,y,z is the host
          Class B: w.x specifies the network and y.z the host.
          Class C: w.x.y specifies the network and z the host.

          Class    First octet pattern
            A          0xxxxxxx       0 through 127
            B          10xxxxxx       128 through 191 (UNI is 134)
            C          110xxxxx       192 through 223

          UNI is a class B network:  134.161.0.0 is the network 
                                                  address, when the
                                                   host bits are masked
                                                    with 255.255.0.0
                                                     class B mask.
          Class A mask:   255.0.0.0
          Class B mask:   255.255.0.0
          Class C mask:   255. 255.255.0

   So when any IP number from UNI is the destination for a packet
      that is out on the internet somewhere and headed to UNI, 
      the subnet mask 255.255.0.0 is used to mask the y.z bits
      of w.x.y.z off, giving 134.161.0.0 as the network address.

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     Practice tests and additional sample questions
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     See http://www.cs.uni.edu/~jacobson/1020/tests

       i. 023FinalCRCquestion.pdf   

               Good practice for Cyclic Redundancy Check (CRC),
                                which we did in class.
                                See your handouts and notes.

      ii. FinalPages1and2_2011.pdf  
               See questions 2, 3, 4, 5, 6, 7, 8 and 9.
               Caesar encrypt/decrypt; networking 7 layers,
               network addresses and NIC/NAC/MAC addresses,
               input and output redirection and pipes.

               IGNORE questions 1, 10, 11 and 12.

     iii. QuizOne2011.pdf        
               TIC practice, Hamming codeword practice, 
               Caesar decrypt and encrypt practice, binary practice.

               IGNORE the very last question, which is
               about Vignere cipher encryption.  We have NOT
               covered that.

      iv. TICquestionFinal023.pdf

               Tiny Imaginary Computer practice.

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      IGNORE THESE THREE files....  Nothing in them for quiz two.
     
           023SubnetMasksFinal.pdf   
           QuizTwoApr5th2011.pdf
           QuizTwoSpr2008.pdf
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