Theoretically, quantum computing offers the possibility of factoring the products of large prime numbers and calculating discreet logarithms in polynomial time. These calculations can be accomplished in such a compressed time frame because:
Correct Answer: D
In digital computers, a bit is in either a one or zero state. In a quantum computer, through linear superposition, a quantum bit can be in both states, essentially simultaneously. Thus, computations consisting of trail evaluations of binary patterns can take place simultaneously in exponential time. The probability of obtaining a correct result is increased through a phenomenon called constructive interference of light while the probability of obtaining an incorrect result is decreased through destructive interference. Answer a describes optical computing that is effective in applying Fourier and other transformations to data to perform high-speed computations. Light representing large volumes of data passing through properly shaped physical objects can be subjected to mathematical transformations and recombined to provide the appropriate results. However, this mode of computation is not defined as quantum computing. Answers c and d are diversionary answers that do not describe quantum computing.
CISSP Exam Question 247
A large bank deploys hardware tokens to all customers that use their online banking system. The token generates and displays a six digit numeric password every 60 seconds. The customers must log into their bank accounts using this numeric password. This is an example of
Correct Answer: D
CISSP Exam Question 248
Which of the following services is NOT provided by the digital signature standard (DSS)?
Correct Answer: A
DSS provides Integrity, digital signature and Authentication, but does not provide Encryption. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 4: Cryptography (page 160).
CISSP Exam Question 249
Which of the following is true about Kerberos?
Correct Answer: C
Kerberos depends on secret keys (symmetric ciphers). Kerberos is a third party authentication protocol. It was designed and developed in the mid 1980's by MIT. It is considered open source but is copyrighted and owned by MIT. It relies on the user's secret keys. The password is used to encrypt and decrypt the keys. The following answers are incorrect: It utilizes public key cryptography. Is incorrect because Kerberos depends on secret keys (symmetric ciphers). It encrypts data after a ticket is granted, but passwords are exchanged in plain text. Is incorrect because the passwords are not exchanged but used for encryption and decryption of the keys. It is a second party authentication system. Is incorrect because Kerberos is a third party authentication system, you authenticate to the third party (Kerberos) and not the system you are accessing. References: MIT http://web.mit.edu/kerberos/ Wikipedi http://en.wikipedia.org/wiki/Kerberos_%28protocol%29 OIG CBK Access Control (pages 181 - 184) AIOv3 Access Control (pages 151 - 155)
CISSP Exam Question 250
In Operations Security trusted paths provide:
Correct Answer: C
The following answers are incorrect: Integrity paths has no meaning in the context of this question. Trusted paths brings to mind the word integrity only in the context that the data was not changed and is in it's orginal condition. This question also has less to do with integration and more to do with actual implementation of a concept. There is less need to create trusted paths to something that is already not secure. MTBF is Mean Time Between Failure. This is not really related to a trusted path therefore not related to this question. The following reference(s) were/was used to create this question: "Trusted paths provide trustworthy interfaces into privledged user functions and are intended to provide a way to ensure that any communications over that path cannot be intercepted or corrupted." pp. 544 Official Guide to the CISSP CBK, Second Edition, copyright 2010, Edited by Harold F. Tipton, Trusted Paths and Fail Secure Mechanisms;
