Problem: An Internet Service Provider (ISP) must, as part of its service to customers, provide a...

 

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Problem: An Internet Service Provider (ISP) must, as part of its service to customers, provide a Domain Name Server (DNS). ADNS is a server that maintains a database of domain names, such as www.griffith.edu.ay, and their corresponding Internet Protocol Addresses (IPA), such as 132.234.243.22 A domain name has only one IPA, but an IPA may have many domain names. Define a class that simulates a DNS. It must have: • a method for updating the DNS with a new domain name and its IPA; a method for returning the IPA for a domain name, or None if it does not exist; and • whatever private attributes are required to support the methods. . Write a test program that allows the user to test the class, by typing in fake domain names and IP As to update the DNS and domain names to look up. An example of the output from the test program is like this: ?u.www.google.com 8.8.8.8 Puwww.amazon.com 2.2.2.2 Pu www.cnn.com Bad command. ?I www.google.com 8.8.8.8 www.amazon.com 2.2.2.2 ? www.cnn.com None 29 where: • u DNS IPA updates the DNS with a new domain name and its IPA; . I DNS returns the IPA for a domain name, or None if it does not exist; and qends the test program. Bad inputs are to be reported and ignored Answer: Submit your code as problemlpy and insert a screenshot of your program output for the following scenario: 7u www.apple.com 10.10.10.10 7 www.tesla.com 11.11.11.11 ?u www.python.org ? I www.apple.com 71 www.python.org 79 Insert picture 1.2 Problem 2 (3 marks) Problem: The government now requires that DNSS should maintain a secret blacklist of IPAs that must not be returned, even if the domain name exists. Without changing your DNS class from problem 1, define a new class that extends your old class, adding: . . a method for adding an IPA to the secret blacklist; and a private attribute for the blacklist. Hint: it may be called a blacklist, but is a Python list the most efficient data structure to use here? You must also override the lookup method so that it returns None for blacklisted IPA, even if they do exist Write a test program that allows the user to test the new class. An example of the output from the test programis like this: . uwww.google.com 8.8.8.8 uwww.amazon.com 2.2.2.2 ?b2.2.2.2 ?Iwww.google.com ?Iwww.amazon.com B.B.B.B None ?g where: u DNS IPA updates the DNS with a new domain name and its IPA; b IPA adds the IPA to the secret blacklist: • I DNS returns the IPA for a domain name, or None if it does not exist or is in the secret blacklist; qends the test program. • Bad inputs are to be reported and ignored. Answer: Submit your code as problem2.py and insert a screenshot of your program output for the following scenario: Problem: An Internet Service Provider (ISP) must, as part of its service to customers, provide a Domain Name Server (DNS). ADNS is a server that maintains a database of domain names, such as www.griffith.edu.ay, and their corresponding Internet Protocol Addresses (IPA), such as 132.234.243.22 A domain name has only one IPA, but an IPA may have many domain names. Define a class that simulates a DNS. It must have: • a method for updating the DNS with a new domain name and its IPA; a method for returning the IPA for a domain name, or None if it does not exist; and • whatever private attributes are required to support the methods. . Write a test program that allows the user to test the class, by typing in fake domain names and IP As to update the DNS and domain names to look up. An example of the output from the test program is like this: ?u.www.google.com 8.8.8.8 Puwww.amazon.com 2.2.2.2 Pu www.cnn.com Bad command. ?I www.google.com 8.8.8.8 www.amazon.com 2.2.2.2 ? www.cnn.com None 29 where: • u DNS IPA updates the DNS with a new domain name and its IPA; . I DNS returns the IPA for a domain name, or None if it does not exist; and qends the test program. Bad inputs are to be reported and ignored Answer: Submit your code as problemlpy and insert a screenshot of your program output for the following scenario: 7u www.apple.com 10.10.10.10 7 www.tesla.com 11.11.11.11 ?u www.python.org ? I www.apple.com 71 www.python.org 79 Insert picture 1.2 Problem 2 (3 marks) Problem: The government now requires that DNSS should maintain a secret blacklist of IPAs that must not be returned, even if the domain name exists. Without changing your DNS class from problem 1, define a new class that extends your old class, adding: . . a method for adding an IPA to the secret blacklist; and a private attribute for the blacklist. Hint: it may be called a blacklist, but is a Python list the most efficient data structure to use here? You must also override the lookup method so that it returns None for blacklisted IPA, even if they do exist Write a test program that allows the user to test the new class. An example of the output from the test programis like this: . uwww.google.com 8.8.8.8 uwww.amazon.com 2.2.2.2 ?b2.2.2.2 ?Iwww.google.com ?Iwww.amazon.com B.B.B.B None ?g where: u DNS IPA updates the DNS with a new domain name and its IPA; b IPA adds the IPA to the secret blacklist: • I DNS returns the IPA for a domain name, or None if it does not exist or is in the secret blacklist; qends the test program. • Bad inputs are to be reported and ignored. Answer: Submit your code as problem2.py and insert a screenshot of your program output for the following scenario:

Answer rating: 100% (QA)

To run the program save it as problem1py and execute it using a Python interpreter It allows you to ... View the full answer