Chapter 31. (60%) Assume an 8-letter password from the 95 printable ASCII characters is used in a computer system.a. If passwords are chosen by the users, what is the total password population? What is the probability of an adversary guessing a password correctly?b. If passwords are generated automatically by a pseudorandom number generator, what is the total password population? What is the probability of an adversary guessing a password correctly?
2. (40%) Explain why, for the biometric authentication protocols, the biometric capture device is authenticated in the case of static biometric but not authenticated for a dynamic biometric.
Chapter 41. (25%) UNIX treats file directories in the same fashion as files; that is, both are defined by the same type of data structure, called an inode. As with files, directories include a nine-bit protection string. If care is not taken, this can create access control problems. For example, consider a file with protection mode 644 (octal) contained in a directory with protection mode 730. How might the file be compromised in this case?(25%) Consider user accounts on a computer system with a Web server configured to provide user Web areas. In general, this uses a standard directory name, such as “public_html,” in a user’s home directory. However, access control needs to be properly set to allow users (with or without user accounts on the system) to browse the webpages. Assuming there are one main page (index.html), two pictures files (a.jpg and b.jpg) stored in an sub-directory (Image) and one pdf file (c.pdf) stored in an sub-directory (Doc), all under the public_html. Specify the access control for each directory and files that allows everyone to view the webpage.
(50%) For the DAC model discussed in Section 4.3, an alternative representation of the protection state is a directed graph. Each subject and each object in the protection state is represented by a node (a single node is used for an entity that is both subject and object). A directed line forms a subject to an object indicates an access right, and the label on the link defines the access right.Draw a directed graph that represented to the access matrix of Figure 4.2a.Draw a directed graph that represented to the access matrix of Figure 4.3.Is there a one-to-one correspondence between the directed graph representation and the access matrix representation? Explain your answer.
Why Choose Us
We value our clients. For this reason, we ensure that each paper is written carefully as per the instructions provided by the client. Our editing team also checks all the papers to ensure that they have been completed as per the expectations.
Professional Academic Writers
Over the years, our Acme Homework has managed to secure the most qualified, reliable and experienced team of writers. The company has also ensured continued training and development of the team members to ensure that it keep up with the rising Academic Trends.
Our prices are fairly priced in such a way that ensures affordability. Additionally, you can get a free price quotation by clicking on the "Place Order" button.
We pay strict attention on deadlines. For this reason, we ensure that all papers are submitted earlier, even before the deadline indicated by the customer. For this reason, the client can go through the work and review everything.
At Graduate Assistants, all papers are plagiarism-free as they are written from scratch. We have taken strict measures to ensure that there is no similarity on all papers and that citations are included as per the standards set.
Customer Support 24/7
Our support team is readily available to provide any guidance/help on our platform at any time of the day/night. Feel free to contact us via the Chat window or support email: firstname.lastname@example.org.
Try it now!
How it works?
Follow these simple steps to get your paper done
Place your order
Fill in the order form and provide all details of your assignment.
Proceed with the payment
Choose the payment system that suits you most.
Receive the final file
Once your paper is ready, we will email it to you.
Graduate Assistants has stood as the world’s leading custom essay writing services providers. Once you enter all the details in the order form under the place order button, the rest is up to us.
At Graduate Assistants, we prioritize on all aspects that bring about a good grade such as impeccable grammar, proper structure, zero-plagiarism and conformance to guidelines. Our experienced team of writers will help you completed your essays and other assignments.
Admission and Business Papers
Be assured that you’ll definitely get accepted to the Master’s level program at any university once you enter all the details in the order form. We won’t leave you here; we will also help you secure a good position in your aspired workplace by creating an outstanding resume or portfolio once you place an order.
Editing and Proofreading
Our skilled editing and writing team will help you restructure you paper, paraphrase, correct grammar and replace plagiarized sections on your paper just on time. The service is geared toward eliminating any mistakes and rather enhancing better quality.
We have writers in almost all fields including the most technical fields. You don’t have to worry about the complexity of your paper. Simply enter as much details as possible in the place order section.