To encrypt the data on the hard drive is the best deterrent for information theft (not however the best for physical theft).

RAID Level 1 often implemented by a one-for-one disk to disk ratio.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten
Domains of Computer Security, 2001, John Wiley & Sons, Page 65.
See Also: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne,
2002, chapter 7: Telecommunications and Network Security (page 480).
See also: “This level duplicates all disk writes from one disk to another to create two identical
drives. This technique is also known as data mirroring. Redundancy is provided at this level”
Source: Official ISC2 Guide to the CISSP CBK. p. 657
=============================
RAID Level 0 – “Writes files in stripes across multiple disks without the use of parity informaiton.
This technique allows for fast reading and writing to disk. However, without parity information, it is
not possible to recover from a hard drive failure.” Source: Official ISC2 Guide to the CISSP CBK.
p. 657 =============================
RAID Level 2 – “Data is spread across multiple disks at the bit level using this technique. Redundancy information is computed using a Hammering error correction code, which is the same technique used within hard drives and error-correcting memory modules.” Source: Official ISC2 guide to the CISSP CBK p.657-658 ============================= RAID Level 5 – “This level requires three or more drives to implement. Data and parity information is striped together across all drives. This level is the most popular and can tolerate the loss of any one drive.” Source: Official ISC2 Guide to the CISSP CBK p. 658

Explanation/Reference:
Explanation:
RAID Level 1, disk mirroring, uses a one-for-one setup, where data are written to two drives at once. If one drive fails, the other drive has the exact same data available.
Incorrect Answers:
B: RAID Level 0 uses data striped over several drives, not just two drives. There is not one-to-one disk ratio.
C: RAID Level 2 uses data striped over several drives, not just two drives. There is not one-to-one disk ratio.
D: RAID Level 5 does not use a one-to-one disk ratio.
References:
Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, p. 1270

The goal to this type of attack is to find the cryptographic key that was used to encrypt the message. Once the key has been found, the attacker would then be able to decrypt all messages that had been encrypted using that key.
The known-plaintext attack (KPA) or crib is an attack model for cryptanalysis where the attacker has samples of both the plaintext and its encrypted version (ciphertext), and is at liberty to make use of them to reveal further secret information such as secret keys and code books. The term “crib” originated at Bletchley Park, the British World War II decryption operation
In cryptography, a brute force attack or exhaustive key search is a strategy that can in theory be used against any encrypted data by an attacker who is unable to take advantage of any weakness in an encryption system that would otherwise make his task easier. It involves systematically checking all possible keys until the correct key is found. In the worst case, this would involve traversing the entire key space, also called search space.
In cryptography, a ciphertext-only attack (COA) or known ciphertext attack is an attack model for cryptanalysis where the attacker is assumed to have access only to a set of ciphertexts.
The attack is completely successful if the corresponding plaintexts can be deduced, or even better, the key. The ability to obtain any information at all about the underlying plaintext is still considered a success. For example, if an adversary is sending ciphertext continuously to maintain traffic-flow security, it would be very useful to be able to distinguish real messages from nulls. Even making an informed guess of the existence of real messages would facilitate traffic analysis.
In the history of cryptography, early ciphers, implemented using pen-and-paper, were routinely broken using ciphertexts alone. Cryptographers developed statistical techniques for attacking ciphertext, such as frequency analysis. Mechanical encryption devices such as Enigma made these attacks much more difficult (although, historically, Polish cryptographers were able to mount a successful ciphertext-only cryptanalysis of the
Enigma by exploiting an insecure protocol for indicating the message settings).
Every modern cipher attempts to provide protection against ciphertext-only attacks. The vetting process for a new cipher design standard usually takes many years and includes exhaustive testing of large quantities of ciphertext for any statistical departure from random noise. See: Advanced Encryption Standard process. Also, the field of steganography evolved, in part, to develop methods like mimic functions that allow one piece of data to adopt the statistical profile of another. Nonetheless poor cipher usage or reliance on home- grown proprietary algorithms that have not been subject to thorough scrutiny has resulted in many computer-age encryption systems that are still subject to ciphertext-only attack.
Examples include:
Early versions of Microsoft’s PPTP virtual private network software used the same RC4 key for the sender and the receiver (later versions had other problems). In any case where a stream cipher like RC4 is used twice with the same key it is open to ciphertext-only attack.
See: stream cipher attack
Wired Equivalent Privacy (WEP), the first security protocol for Wi-Fi, proved vulnerable to several attacks, most of them ciphertext-only.
A chosen-plaintext attack (CPA) is an attack model for cryptanalysis which presumes that the attacker has the capability to choose arbitrary plaintexts to be encrypted and obtain the corresponding ciphertexts. The goal of the attack is to gain some further information which reduces the security of the encryption scheme. In the worst case, a chosen-plaintext attack could reveal the scheme’s secret key.
This appears, at first glance, to be an unrealistic model; it would certainly be unlikely that an attacker could persuade a human cryptographer to encrypt large amounts of plaintexts of the attacker’s choosing. Modern cryptography, on the other hand, is implemented in software or hardware and is used for a diverse range of applications; for many cases, a chosen-plaintext attack is often very feasible. Chosen-plaintext attacks become extremely important in the context of public key cryptography, where the encryption key is public and attackers can encrypt any plaintext they choose.
Any cipher that can prevent chosen-plaintext attacks is then also guaranteed to be secure against known-plaintext and ciphertext-only attacks; this is a conservative approach to security.
Two forms of chosen-plaintext attack can be distinguished:
Batch chosen-plaintext attack, where the cryptanalyst chooses all plaintexts before any of them are encrypted. This is often the meaning of an unqualified use of “chosen-plaintext attack”.
Adaptive chosen-plaintext attack, where the cryptanalyst makes a series of interactive queries, choosing subsequent plaintexts based on the information from the previous encryptions.
References:
Source: TIPTON, Harold, Official (ISC)2 Guide to the CISSP CBK (2007), page 271.
and
Wikipedia at the following links:
http://en.wikipedia.org/wiki/Chosen-plaintext_attack
http://en.wikipedia.org/wiki/Known-plaintext_attack
http://en.wikipedia.org/wiki/Ciphertext-only_attac
http://en.wikipedia.org/wiki/Brute_force_attack

This the best of the four answers as a defense that depends on multiple layers is superior to one where all protection is embedded in a single layer (e.g., a firewall).
Defense in depth would include all categories of controls.
The Following answers are incorrect:
“Concept of a pass through device that only allows certain traffic in and out” is incorrect.
This is one definition of a firewall which can be a component of a defense in depth strategy in combination with other measures.
“Concept of preventative controls” is incorrect. This is a component of a defense in depth strategy but the core concept is that there must be multiple layers of defenses.
“Concept of defensive controls” is incorrect. This is a component of a defense in depth strategy but the core concept is that there must be multiple layers of defenses.
References:
http://en.wikipedia.org/wiki/Defense_in_depth_(computing)
http://www.nsa.gov/snac/support/defenseindepth.pdf

The main task here is the authentic distribution of the new root CA certificate as new trust anchor to all the PKI participants (e.g. the users).
In some of the rollover-scenarios there is no automatic way, often explicit assignment of trust from each user is needed, which could be very costly.
Other methods make use of the old root CA certificate for automatic trust establishment
(see PKIX-reference), but these solutions works only well for scenarios with currently valid root CA certificates (and not for emergency cases e.g. compromise of the current root CA certificate).
The rollover of the root CA certificate is a specific and delicate problem and therefore are often ignored during PKI deployment.
Reference: Camphausen, I.; Petersen, H.; Stark, C.: Konzepte zum Root CA
Zertifikatswechsel, conference Enterprise Security 2002, March 26-27, 2002, Paderborn;
RFC 2459 : Internet X.509 Public Key Infrastructure Certificate and CRL Profile.

The correct answer is “The ability to recover from a reset with the permissions set to cllow all”.
Permissions should be set to deny all
during reset.

Explanation
Section: Security Assessment and Testing

The correct answer is “Carrier Sense Multiple Access”. The other acronyms do not exist.

Because the Reference Monitor is responsible for access control to the objects by the subjects it compares the security labels of a subject and an object.
According to the OIG: The reference monitor is an access control concept referring to an abstract machine that mediates all accesses to objects by subjects based on information in an access control database. The reference monitor must mediate all access, be protected from modification, be verifiable as correct, and must always be invoked. The reference monitor, in accordance with the security policy, controls the checks that are made in the access control database.
The following are incorrect:
Validation Module. A Validation Module is typically found in application source code and is used to
validate data being inputted.
Clearance Check. Is a distractor, there is no such thing other than what someone would do when
checking if someone is authorized to access a secure facility.
Security Module. Is typically a general purpose module that prerforms a variety of security related
functions.
References:
OIG CBK, Security Architecture and Design (page 324)
AIO, 4th Edition, Security Architecture and Design, pp 328-328.
Wikipedia – http://en.wikipedia.org/wiki/Reference_monitor

The answer should be 25 meters:
If a lamp provides a 30 foot illumination, the lamps should be placed less than 30 feet apart to
provide an overlap. A 30 meter coverage area mean the next light should be less than 30 meters
away, and the only answer that fits is 25 meters.
Chapter 6, page 459 of Shon Harris CISSP 5th edition book.

Explanation/Reference:
Explanation:
Three main rules are used and enforced in the Bell-LaPadula model:
The simple security (SS) rule, the *-property (star property) rule, and the strong star property rule. The simple security rule states that a subject at a given security level cannot read data that reside at a higher security level.
The *-property rule (star property rule) states that a subject in a given security level cannot write information to a lower security level. The simple security rule is referred to as the “no read up” rule, and the
*-property rule is referred to as the “no write down” rule.
The third rule, the strong star property rule, states that a subject that has read and write capabilities can only perform those functions at the same security level; nothing higher and nothing lower. So, for a subject to be able to read and write to an object, the clearance and classification must be equal.
Incorrect Answers:
B: The simple security rule is referred to as the “no read up” rule, not the “no write down” rule. The *- property rule is referred to as the “no write down” rule.
C: The simple security rule is referred to as the “no read up” rule, not the “no read down” rule.
D: The simple security rule is referred to as the “no read up” rule, not the “no write up” rule.
References:
Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, pp. 369-370

Denial of Service is an attack on the operating system or software using buffer overflows. The result is that the target is unable to reply to service requests. This is too a large an area of information to try to cover here, so I will limit my discussion to the types of denial of service (DoS) attacks:

RFC 2828 (Internet Security Glossary) defines digital watermarking as computing techniques for inseparably embedding unobtrusive marks or labels as bits in digital data-text, graphics, images, video, or audio#and for detecting or extracting the marks later. The set of embedded bits (the digital watermark) is sometimes hidden, usually imperceptible, and always intended to be unobtrusive. It is used as a measure to protect intellectual property rights. Steganography involves hiding the very existence of a message. A digital signature is a value computed with a cryptographic algorithm and appended to a data object in such a way that any recipient of the data can use the signature to verify the data’s origin and integrity. A digital envelope is a combination of encrypted data and its encryption key in an encrypted form that has been prepared for use of the recipient. Source: SHIREY, Robert W., RFC2828: Internet Security Glossary, may 2000.