Explanation/Reference:
Explanation:
Cheyenne Software (now owned by Computer Associates) was the first to offer RAID 5 for tape devices.
Because by nature tape devices employ a sequential access method, RAID 5 is an ideal solution for a tape array.
Incorrect Answers:
B: A scale array is A RAID backup system.
C: A crimson array is A RAID backup system.
D: A table array is A RAID backup system.

Explanation/Reference:
Explanation:
Port knocking is an authentication method used by network administrators to control access to computers or other network devices behind a firewall. Port knocking takes advantage of firewall rules to allow a client who knows the "secret knock" to enter the network through a particular port by performing a sequence of connection attempts (called a knock sequence). The correct knock sequence for any given port is created for specific IP addresses by the network administrator. A small program called a daemon monitors the firewall log files for connection requests and determines whether or not a client seeking the network is on the list of approved IP addresses and has performed the correct knock sequence. If the answer is yes, it opens the associated port and allows access. Of course, if unauthorized personnel discover the knock sequence, then they, too, can gain access.
Incorrect Answers:
B: Port knocking is not where the user calls the server operator to have him start the service he wants to connect to.
C: Port knocking is not where all the ports are open on the server and the connecting client scans the open port to which he wants to connect to see if it's open and running.
D: Port knocking is not where the port sequence is encrypted with 3DES and only the server has the other key to decrypt the port sequence.
References:
http://whatis.techtarget.com/definition/port-knocking
http://www.portknocking.org/

Explanation/Reference:
Explanation:
Accountability is another facet of access control. Individuals on a system are responsible for their actions.
This accountability property enables system activities to be traced to the proper individuals. Accountability is supported by audit trails that record events on the system and network. Audit trails can be used for intrusion detection and for the reconstruction of past events. Monitoring individual activities, such as keystroke monitoring, should be accomplished in accordance with the company policy and appropriate laws. Banners at the log-on time should notify the user of any monitoring that is being conducted.
Incorrect Answers:
A: Authentication is proof that a user is who they say they are. This is important in accountability. However, you also need to be able to monitor that user's actions. This is provided by audit trails.
B: Integrity ensures that data is consistent and not modified. This does not provide accountability.
C: Confidentiality attempts to prevent the intentional or unintentional unauthorized disclosure of data. This does not provide accountability.
References:
Krutz, Ronald L. and Russell Dean Vines, The CISSP and CAP Prep Guide: Mastering CISSP and CAP, Wiley Publishing, Indianapolis, 2007, p. 72