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These questions are from the discretionary and mandatory acc…

These questions are from the discretionary and mandatory access control modules. All students in a class belong to a group G and are able to access class resources because G is granted the necessary permissions. Assume Alice has tested out of a topic and does not need to take the quiz on this topic. The professor does not want Alice to have access to this quiz but wants Alice to remain in group G so she can access other resources. Also, the professor wants to grant access to the quiz to all other students by granting the desired access to G. The mechanisms provided by various operating systems can be used to meet this access control requirement. Explain how this can be achieved most efficiently and correctly in Linux with extended access control lists (EACLs) and in Windows.  (5+5  pts.) The Bell and La Padula (BLP) and Biba models address confidentiality and integrity of data in a system that supports mandatory access control.. A system follows read down rule of BLP but writes by a user are only allowed at the user’s level (no write to higher levels). Does this system satisfy both confidentiality and integrity as required by the BLP and Biba models? Explain your answer. (3+3 pts.) Is there a drawback to using both of these models at the same time? Provide a brief explanation. (3 pts.) A certain company has many customers and some of them have conflict-of-interest (CoI) relationships. Also, employees can only access company data by executing applications approved by the company based on functions performed by them. The people responsible for access provisioning in this company came up with the following scheme. All files of a given customer must be stored in a single directory. When user U is allowed to  execute an application, the application executing on behalf of U can access files in any directory at the beginning. However, once U’s application accesses files in the directory of a customer C, access to all other directories of  customers who have a CoI relationship with C is turned off for all applications available to U.   Give two examples of policies discussed in the course that could be used to control access to documents by this company? Explain your answer. (4+4 pts.)  Are these policies enforced correctly by the suggested implementation? Provide a brief justification for your answer. (1+3 pts.)

In one well-written paragraph (or more) of 150 words or more…

In one well-written paragraph (or more) of 150 words or more, discuss one literary device demonstrated in Hansberry’s A Raisin in the Sun.  You may create your own thesis or use one of the examples below. Lorraine Hansberry’s A Raisin in the Sun (choose one) In the play A Raisin in the Sun, Lorraine Hansberry uses the characterization of Walter to show that a discontented individual is often unable to take ownership of his life until he realizes that he must set a good example for his children. In the play A Raisin in the Sun, Lorraine Hansberry uses (Walter, Mama, or Beneatha) to develop the theme (that personal integrity is worth more than money or that perseverance is needed to achieve one’s dreams). In the play A Raisin in the Sun, Lorraine Hansberry uses Mama’s houseplant to symbolize the family’s deferred dreams for a better future.