D. The Brewer-Nash model allows access controls to change dynamically based upon a user’s actions. It is often used in environments like Matthew’s to implement a “Chinese wall” between data belonging to different clients.
Image reprinted from CISSP (ISC)2 Certified Information Systems Security Professional Official Study Guide, 7th Edition © John Wiley & Sons 2015, reprinted with permission.
a. Incipient
b. Smoke
c. Flame
d. Heat

A. Fires may be detected as early as the incipient stage. During this stage, air ionization takes place and specialized incipient fire detection systems can identify these changes to provide early warning of a fire.
A. Closed circuit television (CCTV) systems act as a secondary verification mechanism for physical presence because they allow security officials to view the interior of the facility when a motion alarm sounds to determine the current occupants and their activities.
B. In an m of n control system, at least m of n possible escrow agents must collaborate to retrieve an encryption key from the escrow database.
A. This is an example of a vendor offering a fully functional application as a web-based service. Therefore, it fits under the definition of Software as a Service (SaaS). In Infrastructure as a Service (IaaS), Compute as a Service (CaaS), and Platform as a Service (PaaS) approaches, the customer provides their own software. In this example, the vendor is providing the email software, so none of those choices are appropriate.
B. The Digital Signature Standard approves three encryption algorithms for use in digital signatures: the Digital Signature Algorithm (DSA); the Rivest, Shamir, Adleman (RSA) algorithm; and the Elliptic Curve DSA (ECDSA) algorithm. HAVAL is a hash function, not an encryption algorithm. While hash functions are used as part of the digital signature process, they do not provide encryption.
A. In the subject/object model of access control, the user or process making the request for a resource is the subject of that request. In this example, Harry is requesting resource access and is, therefore, the subject.
C. Michael should conduct his investigation, but there is a pressing business need to bring the website back online. The most reasonable course of action would be to take a snapshot of the compromised system and use the snapshot for the investigation, restoring the website to operation as quickly as possible while using the results of the investigation to improve the security of the site.
C. The use of a sandbox is an example of confinement, where the system restricts the access of a particular process to limit its ability to affect other processes running on the same system.
D. Assurance is the degree of confidence that an organization has that its security controls are correctly implemented. It must be continually monitored and re-verified.
A. Maintenance hooks, otherwise known as backdoors, provide developers with easy access to a system, bypassing normal security controls. If not removed prior to finalizing code, they pose a significant security vulnerability if an attacker discovers the maintenance hook.

a. Simple Security Property
b. Simple Integrity Property
c. *-Security Property
d. *-Integrity Property
B. The Simple Integrity Property states that an individual may not read a file classified at a lower security level than the individual’s security clearance.
B. Supervisory control and data acquisition (SCADA) systems are used to control and gather data from industrial processes. They are commonly found in power plants and other industrial environments.
B. The Trusted Platform Module (TPM) is a hardware security technique that stores an encryption key on a chip on the motherboard and prevents someone from accessing an encrypted drive by installing it in another computer.
B. Running DES three times produces a strong encryption standard known as Triple DES, or 3DES. In order for this to provide additional security, DES must also be run using at least two different keys. NIST recommends use of three independent keys for the strongest version.
Questions 16–19 refer to the following scenario.
Alice and Bob would like to use an asymmetric cryptosystem to communicate with each other. They are located in different parts of the country but have exchanged encryption keys by using digital certificates signed by a mutually trusted certificate authority.
C. In an asymmetric cryptosystem, the sender of a message always encrypts the message using the recipient’s public key.
Questions 16–19 refer to the following scenario.
Alice and Bob would like to use an asymmetric cryptosystem to communicate with each other. They are located in different parts of the country but have exchanged encryption keys by using digital certificates signed by a mutually trusted certificate authority.
D. When Bob receives the message, he uses his own private key to decrypt it. Since he is the only one with his private key, he is theB.
Questions 16–19 refer to the following scenario.
Alice and Bob would like to use an asymmetric cryptosystem to communicate with each other. They are located in different parts of the country but have exchanged encryption keys by using digital certificates signed by a mutually trusted certificate authority.
B. Each user retains their private key as secret information. In this scenario, Bob would only have access to his own private key and would not have access to the private key of Alice or any other user.
Questions 16–19 refer to the following scenario.
Alice and Bob would like to use an asymmetric cryptosystem to communicate with each other. They are located in different parts of the country but have exchanged encryption keys by using digital certificates signed by a mutually trusted certificate authority.
B. Alice creates the digital signature using her own private key. Then Bob, or any other user, can verify the digital signature using Alice’s public key.
B. The salt is a random value added to a password before it is hashed by the operating system. The salt is then stored in a password file with the hashed password. This increases the complexity of cryptanalytic attacks by negating the usefulness of attacks that use precomputed hash values, such as rainbow tables.
A. Hash functions do not include any element of secrecy and, therefore, do not require a cryptographic key.
D. A preaction fire suppression system activates in two steps. The pipes fill with water once the early signs of a fire are detected. The system does not dispense water until heat sensors on the sprinkler heads trigger the second phase.
B. The Encapsulating Security Payload (ESP) protocol provides confidentiality and integrity for packet contents. It encrypts packet payloads and provides limited authentication and protection against replay attacks.
D. The greatest risk when a device is lost or stolen is that sensitive data contained on the device will fall into the wrong hands. Confidentiality protects against this risk.