Explanation/Reference:
Explanation:
Kerberos is a trusted, third party authentication protocol that was developed under Project Athena at MIT.
In Greek mythology, Kerberos is a three-headed dog that guards the entrance to the Underworld. Using symmetric key cryptography, Kerberos authenticates clients to other entities on a network of which a client requires services.
Kerberos addresses the confidentiality and integrity of information. It does not address availability.
Incorrect Answers:
B: Kerberos does address integrity.
C: Kerberos does make use of Symmetric Keys.
D: Kerberos does address confidentiality of information.
References:
Krutz, Ronald L. and Russell Dean Vines, The CISSP and CAP Prep Guide: Mastering CISSP and CAP, Wiley Publishing, Indianapolis, 2007, p. 78

In general, reliability (systemic def.) is the ability of a person or system to perform and maintain its functions in routine circumstances, as well as hostile or unexpected circumstances.
Mean-time-between failure (MTBF) is the average length of time the hardware is functional without failure. Mean-time-to-repair is the amount of time it takes to repair and resume normal operation after a failure has occurred. Having a higher MTBF and a lower MTTR will increase the reliability of a piece of equipment, thus the system's overall reliability. Source: VALLABHANENI, S. Rao, CISSP Examination Textbooks, Volume 2: Practice, SRV Professional Publications, 2002, Chapter 8, Business Continuity Planning & Disaster Recovery Planning (page 496). also see: http://en.wikipedia.org/wiki/Reliability

Section: Security Architecture and Engineering

L2F (Layer 2 Forwarding) provides no authentication or encryption. It is a Protocol that supports the creation of secure virtual private dial-up networks over the Internet.
At one point L2F was merged with PPTP to produce L2TP to be used on networks and not only on
dial up links.
IPSec is now considered the best VPN solution for IP environments.
Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002,
Chapter 8: Cryptography (page 507).

Section: Security Architecture and Engineering