Computer Security

Computer Security

Principles and Practice

QUESTION 1

identified and Answers identified as 1, 2, 3…   For each Definition, determine the best Answer.  For each Definition, enter the number corresponding to your answer.  Note: The same best Answer can exist for more than one Definition. Also there may be more than one best Answer.

 

 

 

 

 

 

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Q2 .In a stack architecture CPU an executable program is instantiated as shown in the figure.

 

In what type of memory is this program instantiated?  (answer is an acronym)   

What is located in the .text area? (answer is an acronym or a 1-2 word answer) 

Suppose that the following C code has successfully compiled with the following parameters:

Size of .data space = 20 bytes        Size of .bss space = 7 bytes
Size of heap space = 6 bytes        Size of unused space = 12 bytes
Size of stack space = 10 byte

Assume successful compiling and no exception conditions upon execution.

 

Where does the upper bound of the buffer overflow end? 

1. .data
2. .bss
3. Heap
4. Unused
5. Slack
6. Env/Arg

 

By replacing some of the text “Buffer overflow?” with an address to the beginning of malware code, a hacker could cause malicious code to run.  Answer this as true or false. Answer with a single letter, T for true or F for false.

 

Q3.Personal authentication parameters can be based upon a number of different factors.  These factors can be divided into a several broad classes.  Identify these broad classes and give an example of each.  Put your answer in the table below. Include all that S&B discuss even though not emphasized by instructor.

IMPORTANT: The left column requires one word answers. The answers must be in alphabetical order and spelled correctly in order to get credit. The class containing the phrase “per textbook” is discussed in Stallings and Brown (S&B) but not emphasized by instructor. If you don’t know an answer in the left column, leave the entire  row blank so that you don’t get the others out of alphabetical order, which will result in your subsequent answers being marked wrong.

Class of Authentication Parameter	Authentication Parameter Example
Something that you	An example for this class is
Something that you , per textbook	An example for this class is
Something that you	An example for this class is
Something that you	An example for this class is

 

 

Q4:

 

Q5:You have access to a very limited stateful packet filter.  In addition to the usual stateless filtering, this filter is capable of remembering exactly one IP address that it remembers from a previous outward-bound TCP SYN segment.  Call the remembered IP address “X”.  The filter is located at the interface between your Intranet and the Internet.

You want to design a set of filtering rules that allows a web browser in your Intranet to connect to an arbitrary web server outside, interact with it until one of the two disconnects.  Only one web browser at a time can access the Internet.

 

Figure 1 shows how this can be done using 10 filter rules affording some protection such as assuring that the web server that the browser originally accessed is the only server allowed into the Intranet. (a = any. P = pass. D = drop.)

Show how the same filtering can be done in using only 4 rules.  Show this by providing answers to all the entries as numbered in Figure 2.

 

 

 

The correct answers to all of the questions are included in the following list.

6  17  9   8080  80  X  1023  >1023  <1023  a  1  0

216.47.140.0

The answer to Figure2, item 01 is .

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The answer to Figure2, item 04 is .

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The answer to Figure2, item 35 is .

The answer to Figure2, item 36 is .

 

Q6:

QUESTION 9

1. Analytical studies and laboratory experiments both have strongly implied a threat may be coming for the security of RSA and asymmetric encryption generally.  What is this threat?

Hint: A two-word answer is sufficient.

 

In the BB84 quantum key distribution (QKD) system, complete the following two statements regarding the encoding and transmission of qubits:

Number of spin polarization bases used  =

Number of spin polarizations used   =

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Q10: