Domain 3.3: Security Architecture and Engineering

Question 1

Define:

Salt

Answer 1

Random data added to a password before hashing, enhancing security against cracking.

A random string of characters added to a password before it is hashed. It is used in cryptography to make it more difficult for attackers to crack hashed passwords. Examples of salt include adding a string of random numbers to a password before it is hashed or using a unique salt for each password in a database.

For more information, view this lecture on Hashing- Part 2. Or visit this Wikipedia page.

Question 2

Define:

Sandbox

Answer 2

A controlled environment for safely running untrusted programs or code without risking the integrity of the host system.

A controlled environment used for testing or running potentially dangerous or suspicious code. It is used in cybersecurity to prevent malicious software from damaging systems or networks. Examples include a web browser’s sandbox for running untrusted code, a malware analysis sandbox for studying malware behavior, and a network sandbox for testing new security protocols.

For more information, view this lecture on Web architecture and attacks. Or visit this Wikipedia page.

Question 3

Define:

SCADA

(Supervisory Control And Data Acquisition)

Answer 3

Systems used for monitoring and controlling industrial processes and critical infrastructure.

A system used to monitor and control industrial processes and infrastructure, such as power plants, water treatment facilities, and transportation networks. It is used to automate and remotely manage complex systems and processes. Examples include a SCADA system for monitoring and controlling a power grid, a SCADA system for managing a water treatment plant, and a SCADA system for coordinating traffic signals in a city.

For more information, view this lecture on Industrial Control Systems. Or visit this Wikipedia page.

Question 4

Define:

Scalability in Cloud Computing

Answer 4

The ability to easily expand or decrease IT resources as needed to accommodate changing demands without impacting performance.

The ability to handle an increased workload without a decrease in performance. This concept is used in cloud computing to ensure that a system can handle the added demand of new users or applications without slowing down. For example, a company might need to add new users to its cloud-based email system without disrupting service for existing users.

For more information, view this lecture on Secure Access Service Edge. Or visit this Wikipedia page.

Question 5

Define:

Secure Boot

Answer 5

Secure Boot ensures a device starts with trusted software by verifying cryptographic signatures during the boot process, preventing unauthorized or tampered firmware from loading.

Commonly used in modern PCs, mobile devices, and embedded systems, Secure Boot relies on hierarchical key management. The firmware checks the bootloader, which then checks the operating system kernel. If any component is invalid, the boot process halts. This chain of trust protects against rootkits and other low-level malware. Administrators can further customize key settings to allow or block specific OS versions or custom software.

For more information, visit this Wikipedia page.

Question 6

Define:

Secure Cryptoprocessors

Answer 6

Dedicated hardware components designed to handle sensitive cryptographic operations and protect against physical attacks.

Hardware components designed to securely handle sensitive data such as cryptographic keys and personal identification numbers (PINs). They are embedded in tamper-resistant packaging to prevent physical attacks and are integral to the security of systems processing transactions, authentication credentials, and other critical data.

For more information, view this lecture on Hardware architecture- Part 2. Or visit this Wikipedia page.

Question 7

Define:

Secure Defaults

(or Secure-By-Default)

Answer 7

The practice of pre-configuring systems or applications with the most secure settings to minimize risk.

The practice of setting security settings to the most secure option as the default so that users do not have to manually adjust them. This is used in software and system design, as well as in network and device configuration. For example, a password manager may have a secure default password length requirement, or a router may have a secure default firewall configuration.

For more information, view this lecture on Secure design principles. Or visit this Wikipedia page.

Question 8

Define:

Secure Enclave

Answer 8

A secure enclave is a hardware-based environment—often within CPUs—that isolates sensitive data and operations from the main operating system, protecting them from unauthorized access.

Examples include Apple’s Secure Enclave for biometric data or Intel SGX for confidential computing. These enclaves encrypt stored information and restrict code execution to verified components. Even if the larger OS is compromised, enclave data remains shielded. This design underpins secure key storage, digital rights management, and cryptographic computations, bolstering user privacy and system integrity.

For more information, visit this Wikipedia page.

Question 9

Define:

Secure Enclave

Answer 9

A hardware-isolated area for processing sensitive data securely.

A secure enclave is a dedicated, isolated region within a processor that handles sensitive computations and data in a protected environment. It prevents unauthorized access and mitigates risks from software vulnerabilities by keeping critical operations separate from the main system. Secure enclaves are increasingly used in modern devices to safeguard cryptographic keys, personal data, and other confidential operations against sophisticated attacks.

For more information, visit this Wikipedia page.

Question 10

Define:

Secure Hash Algorithm

(SHA)

Answer 10

A family of cryptographic hash functions used for data integrity, including SHA-1, SHA-2, and SHA-3.

A group of cryptographic hash functions designed to ensure data integrity. By producing a fixed-size hash value from variable input data, SHA helps verify unchanged data transfer, confirm file authenticity, and securely store passwords.

For more information, view this lecture on Hashing- Part 2. Or visit this Wikipedia page.

Question 11

Define:

Secure Hash Algorithm-3

Answer 11

A cryptographic hash function announced as the winner of the NIST hash function competition, offering improved performance.

A cryptographic hash function that was announced as the winner of the NIST hash function competition in 2012. Despite being part of the same family, SHA-3 is fundamentally different from SHA-1 and SHA-2, offering better performance and resistance against potential vulnerabilities. SHA-3 can be used for creating hash values to ensure data integrity, generating unique identifiers for data, and creating digital signatures, among other uses.

For more information, view this lecture on Hashing- Part 2. Or visit this Wikipedia page.

Question 12

Define:

Secure Hash Standard

Answer 12

Cryptographic hash functions standardized by NIST, including SHA-1, SHA-2, and SHA-3, for data integrity verification.

A set of cryptographic hash functions that include SHA-1, SHA-2, and SHA-3, as approved and published by the National Institute of Standards and Technology (NIST) in the United States. These algorithms are widely used to verify data integrity and authenticity. The Secure Hash Standard plays a critical role in many security protocols and applications to provide assurances of data integrity.

For more information, view this lecture on Hashing- Part 2. Or visit this Wikipedia page.

Question 13

Define:

Secure Hashing Algorithm

(SHA-1)

Answer 13

A hashing algorithm producing a 160-bit hash value, previously used for security applications but now considered vulnerable.

A cryptographic hash function that produces a 160-bit hash value, which is typically rendered as a 40-digit hexadecimal number. SHA-1 is part of the Secure Hash Algorithm family designed by the National Security Agency (NSA) and published by the National Institute of Standards and Technology (NIST). It was widely used for security applications and protocols, including TLS and SSL, PGP, SSH, and IPsec. However, SHA-1 is no longer considered secure against well-funded attackers; as of 2005, theoretical weaknesses were discovered, and over time, practical attacks have demonstrated the ability to produce collisions (two different inputs that result in the same hash value). As a result, it has been recommended to transition to stronger hash functions such as SHA-256 or SHA-3.

For more information, view this lecture on Hashing- Part 2. Or visit this Wikipedia page.

Question 14

Define:

Secure Multi-Party Computation

(SMPC)

Answer 14

SMPC lets multiple parties jointly compute a function over their inputs while keeping each input private, using cryptographic protocols that shield individual data.

This enables collaborative tasks—like analytics or machine learning on shared datasets—without revealing raw data or sensitive details. Techniques include secret sharing and homomorphic encryption, distributing computations across parties so no single entity sees the others’ full data. SMPC helps organizations comply with strict privacy regulations while benefiting from shared insights. It’s particularly relevant for healthcare, finance, and consortium-based analytics where confidentiality is crucial.

For more information, visit this Wikipedia page.

Question 15

Define:

Secure State

Answer 15

A condition where an information system is adequately protected against unauthorized access and potential threats.

A state of security in which an information system is protected against unauthorized access, use, disclosure, disruption, modification, or destruction. It is used in security planning and risk management. Examples include the secure state of a computer system, the secure state of a network, and the secure state of a building.

Question 16

Define:

Secure Subsystem

Answer 16

A system component designed to safeguard against unauthorized access and ensure the overall protection of the system.

A subsystem of an information system that is designed and implemented to protect the system against unauthorized access, use, disclosure, disruption, modification, or destruction. It is used in security architecture and design. Examples include firewalls, intrusion detection systems, and encryption algorithms.

Question 17

Define:

Security as a Service

(SECaaS)

Answer 17

A cloud model delivering security services over the internet, simplifying security management for organizations.

A model of delivering security services over the internet. It is used in cloud computing, managed security services, and other internet-based security solutions. Examples include email encryption services, antivirus services, and identity and access management services.

For more information, visit this Wikipedia page.

Question 18

Define:

Security by Design

Answer 18

Security by Design embeds protective measures and threat considerations early in development cycles, ensuring secure architectures rather than retrofitting defenses later.

Instead of adding security controls after products or systems are built, Security by Design involves proactive threat modeling, secure coding, and continuous risk assessment at every phase. This fosters robust applications resistant to common attack vectors. Emphasizing security from the outset lowers remediation costs, shortens patch cycles, and aligns closely with regulatory demands. Ultimately, it cultivates a culture of prevention over reaction, improving trust and lowering vulnerability exposure.

For more information, visit this Wikipedia page.

Question 19

Define:

Security Design

Answer 19

The process of architecting systems, applications, and infrastructure with security as a core concern.

The process and practice of planning and creating systems, applications, and infrastructure with security as a central concern. Security design encompasses a range of activities, from the initial conceptualization of a system to detailed architecture and implementation. It involves identifying potential threats, defining security requirements, and selecting appropriate security controls to mitigate risks to an acceptable level. Good security design aims to achieve a balance between security measures and usability, ensuring robust defense against attacks while maintaining functionality and performance. It incorporates principles such as least privilege, defense in depth, and redundancy and is an essential aspect of developing secure IT systems and applications.

Question 20

Define:

Security Guards

Answer 20

Security guards are trained personnel tasked with protecting premises, assets, and individuals by monitoring, patrolling, and responding to security incidents.

They often collaborate with electronic surveillance systems, coordinate visitor access, and enforce organizational policies. Physical presence deters potential intruders and provides a frontline response to threats like theft, vandalism, or unauthorized entry. Effective programs integrate guard operations with broader security frameworks, promoting rapid incident escalation and thorough documentation. Well-equipped, vigilant guards reinforce both employee safety and asset protection.

For more information, view this lecture on Physical security- Part 1. Or visit this Wikipedia page.

Question 21

Define:

Security Kernel

Answer 21

The central part of a secure operating system that enforces security policy and protects critical functions.

The core component of a secure operating system that enforces the security policy for the entire system. It provides mechanisms such as authentication and access control and is designed to be tamper-proof and resilient to attacks, isolating critical security functions from the rest of the system.

For more information, view this lecture on Secure system design concepts. Or visit this Wikipedia page.

Question 22

Define:

Security Models

Answer 22

Frameworks outlining structures and processes needed to enforce security policies within an organization’s IT environment.

Conceptual frameworks that outline the structures and processes needed to enforce security policies within an organization’s IT environment. Security models help guide the design and implementation of system security by establishing clear rules and protocols for data confidentiality, integrity, and availability.

For more information, view this lecture on Security models and concepts - Introduction Or visit this Wikipedia page.

Question 23

Define:

Security Perimeter

Answer 23

The boundary that defines where an organization’s security controls are enforced, guarding against external threats.

A boundary that defines the physical or logical limits where an organization’s security controls are enforced. The security perimeter guards against external threats and often includes firewalls, IDS/IPS, and access control lists to prevent unauthorized access.

For more information, view this lecture on Physical security- Part 5..

Question 24

Define:

Security Target

Answer 24

A document outlining the security requirements and objectives of a system and the controls implemented to meet them.

A document that outlines the security requirements and objectives of a system or product and specifies how the security controls are implemented and tested. Used in product development and certification. Examples -Security target for a cloud computing service, security target for a mobile app, security target for a network security device.

For more information, view this lecture on Security Evaluation Models. Or visit this Wikipedia page.

Question 25

# Define: Security Template

Answer 25

A predefined configuration file defining security settings that can be applied to systems to maintain consistent security. ## Footnote A predefined configuration file used to define and manage security settings on a network or within an organization. It includes configurations for various policies, user rights, and system services, which can be applied to systems to maintain consistency and facilitate easier management of security settings. Frequently utilized in environments using Microsoft Windows, these templates assist administrators in the deployment and enforcement of corporate security policies.

Question 26

# Define: Self-Encrypting Drive | (SED)

Answer 26

A storage device that automatically encrypts the data it stores, often using hardware-based encryption. ## Footnote A storage device that automatically encrypts the data it contains without requiring any action from the user. It employs hardware-based encryption, where the encryption key is never stored in the computer's operating system. Instead, the key is kept within the drive's controller. This feature offers significant protection against data breaches, especially in cases where physical drives are lost or stolen, as it renders the data unreadable without the correct encryption key. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Self-encrypting_drive).*

Question 27

# Define: Self-Signed Certificates

Answer 27

Certificates issued and signed by the entity that creates them. ## Footnote Self-signed certificates are digital certificates generated and signed by the organization or individual using them rather than by a trusted certificate authority. They enable encrypted communications and identity verification in controlled environments, such as development or internal networks, though they may trigger security warnings when used externally. Their validation relies entirely on the issuer's credibility rather than third-party oversight. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Self-signed_certificate).*

Question 28

# Define: SELinux

Answer 28

Security-Enhanced Linux (SELinux) is a Linux kernel security module that enforces mandatory access control policies, confining processes and limiting their privileges to mitigate exploits. ## Footnote Initially developed by the NSA, SELinux sets fine-grained rules dictating which resources each process can access, preventing breaches from escalating. Configuration can be complex, so administrators define policies carefully. When properly managed, SELinux thwarts privilege escalation and zero-day attacks. Many modern Linux distributions incorporate SELinux by default, offering robust protections against unauthorized file and system modifications. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/SELinux).*

Question 29

# Define: Server Hardening Guidelines

Answer 29

Best practices for securing a server to protect it against vulnerabilities and attacks. ## Footnote The guidelines and best practices for securing a server and protecting it against potential vulnerabilities and attacks. They are used in the configuration and maintenance of servers in a network. Examples of server hardening guidelines include disabling unnecessary services, implementing firewalls and intrusion detection systems, and regularly updating software and patches. *For more information, view this lecture on [Asset Tracking and Hardware Hardening](https://courses.thorteaches.com/courses/take/cissp/lessons/20679155-asset-tracking-and-hardware-hardening).*

Question 30

# Define: Server Side Attacks

Answer 30

Attacks targeting vulnerabilities in server-side applications or services. ## Footnote Server side attacks exploit weaknesses in the applications, services, or configurations hosted on servers. These attacks can compromise sensitive data, disrupt operations, or provide unauthorized access by leveraging vulnerabilities such as injection flaws or misconfigurations, highlighting the importance of regular security updates and rigorous system hardening measures. *For more information, view this lecture on [Malware- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18684286-malware-part-2).*

Question 31

# Define: Serverless Computing

Answer 31

Serverless computing abstracts away server management tasks, letting developers run code in ephemeral environments triggered by events, paying only for actual execution time. ## Footnote Providers handle infrastructure provisioning, capacity scaling, and patching, allowing teams to focus on application logic. Functions-as-a-Service platforms like AWS Lambda exemplify this model. While it simplifies deployments and can reduce costs, complexities arise in monitoring, debugging, and cold-start latency. Security responsibilities shift to managing identities, event triggers, and code integrity. Done well, serverless fosters rapid, highly scalable application deployments. *For more information, view this lecture on [Hardware Architecture- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18591307-hardware-architecture-part-3). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Serverless_computing).*

Question 32

# Define: Service Oriented Architecture | (SOA)

Answer 32

An architectural approach that enables the creation and combination of interoperable services within a system. ## Footnote A design approach that allows for the creation of independent, modular services that can be combined to create a larger application. It is used in software development to create scalable, flexible systems. Examples include Amazon's cloud services and the use of microservices in web applications. *For more information, view this lecture on [Web Architecture and Attacks](https://courses.thorteaches.com/courses/take/cissp/lessons/19148725-web-architecture-and-attacks). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Service-oriented_architecture).*

Question 33

# Define: Session Fixation

Answer 33

A cyber-attack exploiting session ID manipulation to gain unauthorized account access. ## Footnote A type of attack where an attacker manipulates the session identifier, or "session ID," of a user's session to gain unauthorized access to their account. It is often used in web-based attacks, where the attacker may trick a user into using a compromised session ID. For instance, an attacker may send a user a malicious link with a pre-set session ID, allowing the attacker to hijack the user's session. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Session_fixation).*

Question 34

# Define: Session Hijacking

Answer 34

An attack intercepting and taking over a legitimate session between a user and a system. ## Footnote An attack where an intruder takes over a valid session between a user and a system. The attacker exploits vulnerabilities in the session management, such as weak session IDs or unprotected network traffic, to impersonate the user. Once control is gained, the attacker can perform actions as the authenticated user, potentially leading to unauthorized access to sensitive information or functionality. *For more information, view this lecture on [Attacks on Our Cryptography- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149711-attacks-on-our-cryptography-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Session_hijacking).*

Question 35

# Define: Session Key

Answer 35

A temporary key used to encrypt communication during a session, ensuring secure data transfer. ## Footnote A temporary encryption key used for secure communication between two parties during a single session. It is used in cryptography to provide secure communication without the need for long-term keys. Examples include the use of session keys in SSL/TLS communications and in SSH connections. *For more information, view this lecture on [The Encryption We Use Today](https://courses.thorteaches.com/courses/take/cissp/lessons/19215118-the-encryption-we-use-today). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Session_key).*

Question 36

# Define: Shared Key Authentication | (SKA)

Answer 36

An older method of wireless network authentication using a pre-shared secret key. ## Footnote An outdated wireless authentication method where both the client and the access point must possess a pre-shared secret key. The protocol is vulnerable to several security issues and is no longer recommended for use in secure wireless environments, with modern protocols like WPA2 and WPA3 providing stronger security measures. *For more information, view this lecture on [The Encryption We Use Today](https://courses.thorteaches.com/courses/take/cissp/lessons/19215118-the-encryption-we-use-today).*

Question 37

# Define: Shared Tenancy

Answer 37

An arrangement where multiple users share infrastructure while keeping data separated. ## Footnote Shared Tenancy describes a model in which several organizations or users share the same physical or virtual infrastructure while maintaining isolated data environments. Commonly seen in cloud services, this approach optimizes resource utilization and cost efficiency. However, it requires stringent security measures to ensure that each tenant’s data remains protected and segregated from others, safeguarding confidentiality and integrity. *For more information, view this lecture on [Site Selection- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149825-site-selection-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Lease).*

Question 38

# Define: Shared-Secret Encryption

Answer 38

An encryption method where the same key is used for both encryption and decryption. ## Footnote A type of encryption where the same secret key is used by both the sender and the receiver to encrypt and decrypt messages. It is often used in symmetric-key cryptography, where the same secret key is used by both parties to encrypt and decrypt messages. For instance, in a shared-secret encryption system, the sender and receiver may agree on a secret key and use that key to encrypt and decrypt messages sent between them. *For more information, view this lecture on [The Encryption We Use Today](https://courses.thorteaches.com/courses/take/cissp/lessons/19215118-the-encryption-we-use-today). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Symmetric-key_algorithm).*

Question 39

# Define: Shell

Answer 39

A user interface for accessing an operating system's services, often command-line based. ## Footnote A command-line interface for accessing an operating system's services. It is used to perform tasks and manage system resources through the use of commands and scripts. Examples include the Bash shell on Linux systems and the PowerShell on Windows systems. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Shell_(computing)).*

Question 40

# Define: Shielded Enclosure

Answer 40

A protective case that blocks electromagnetic interference to protect electronic equipment. ## Footnote A protective covering or enclosure that is designed to block electromagnetic interference (EMI). It is used in electrical and electronic systems to prevent EMI from affecting the operation of the system. Examples include shielded cables and enclosures for sensitive electronic equipment. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Faraday_cage).*

Question 41

# Define: Shimmer

Answer 41

A skimming device inserted into card slots to steal data from chip-based credit or debit cards. ## Footnote A type of skimming device that is inserted into a card slot, such as those on ATMs or point-of-sale terminals, to read data from chip-based credit and debit cards. Unlike traditional skimmers, shimmers are thinner and target the chip instead of the magnetic stripe, making them harder to detect.

Question 42

# Define: Side Channel Attacks

Answer 42

Exploits that use indirect information from a system to uncover sensitive data or keys. ## Footnote Security attacks that exploit indirect information gained from a system's implementation, such as power consumption or electromagnetic emissions, to compromise the system. While side-channel attacks can occur in various environments, including virtualized systems, they are not exclusive to virtualization and can affect physical hardware as well. *For more information, view this lecture on [Attacks on Our Cryptography- Part 3](https://courses.thorteaches.com/courses/take/cissp/lessons/19423096-attacks-on-our-cryptography-part-3). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Side-channel_attack).*

Question 43

# Define: SIGABA

Answer 43

A cipher machine used by the U.S. during WWII for secure communications. ## Footnote SIGABA was a sophisticated encryption machine deployed by the United States during World War II. Its complex system of rotors and switching mechanisms provided robust and secure communication for military operations, ensuring that sensitive messages remained confidential against enemy decryption efforts. *For more information, view this lecture on [The History of Cryptography- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19215103-the-history-of-cryptography-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/SIGABA).*

Question 44

# Define: Signature Detection

Answer 44

Identifying threats by comparing attributes to a database of known malicious signatures. ## Footnote A method of identifying known threats or malicious software by comparing their characteristics, such as code or behavior, to a database of known signatures. It is commonly used in antivirus software and other security tools to quickly identify and remove known threats. Examples include signature detection, used to identify and remove malware from a computer, signature detection used to detect and block phishing emails; and signature detection, used to identify and block malicious websites. *For more information, view this lecture on [Malware- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18684286-malware-part-2).*

Question 45

# Define: Simple Security Property

Answer 45

A rule in the Bell-LaPadula security model that restricts access based on security levels to protect data confidentiality. ## Footnote A term used in the Bell-LaPadula (BLP) security model, a formal model for maintaining confidentiality in a system. The Simple Security Property, also known as the no-read-up, no-write-down (NRU, NWD) rule, states that a subject (a user or a process operating on behalf of a user) cannot read an object (information or a resource) at a higher security level, nor write to an object at a lower security level. This is to prevent sensitive information from being accessed by unauthorized users or downgraded to a less secure level, hence ensuring the confidentiality of data. *For more information, view this lecture on [Security Models and Concepts - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/47772487-security-models-and-concepts-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Bell–LaPadula_model).*

Question 46

# Define: Site Marking

Answer 46

The practice of labeling areas to designate zones and guide access within a site. ## Footnote Site Marking involves the application of visual indicators, such as signs, paint, or physical barriers, to clearly delineate different zones within a property. It is used to identify restricted areas, hazard zones, or operational sections, thereby enhancing security, safety, and organizational efficiency. Effective site marking helps prevent unauthorized access and aids in emergency management by providing clear navigational cues. *For more information, view this lecture on [Site Selection- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149825-site-selection-part-1).*

Question 47

# Define: Skimmer

Answer 47

A device used to illicitly capture credit card information from card readers at points of transaction like ATMs or gas pumps. ## Footnote A device that is attached to a card reader, such as an ATM or gas pump, to steal credit card information. It is used in instances of credit card fraud. Examples include skimmers attached to gas pumps, ATMs, and point-of-sale systems. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Credit_card_fraud#Skimming).*

Question 48

# Define: Slab to Slab Walls

Answer 48

Continuous walls extending between building floors to provide support and fire resistance. ## Footnote Slab to Slab walls are structural elements that extend continuously from one floor slab to another, providing critical support, rigidity, and fire protection within a building. These walls help distribute loads evenly and act as barriers to the spread of fire and smoke. Their design is essential in modern construction, contributing both to the stability and safety of multi-story structures. *For more information, view this lecture on [Physical Security- Part 5](https://courses.thorteaches.com/courses/take/cissp/lessons/19149815-physical-security-part-5).*

Question 49

# Define: Smishing

Answer 49

A social engineering attack delivered via SMS messages, luring recipients into divulging personal information or clicking malicious links. ## Footnote Similar to phishing emails, attackers pose as trusted entities—banks, service providers, or government agencies. Victims may unknowingly reveal credentials, financial details, or install malware. Defensive measures include verifying message authenticity, avoiding unverified links, and enabling spam filters. Raising awareness about smishing helps users recognize suspicious texts and question urgent requests that might indicate an evolving cyber scam. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Phishing#SMS_phishing).

Question 50

# Define: Software as a Service | (SaaS)

Answer 50

A cloud computing model where software applications are delivered online on a subscription basis. ## Footnote A type of cloud computing model where a provider delivers software applications to users over the internet on a subscription basis. It is commonly used by businesses to access software applications without the need to install and maintain them on their own premises. Examples of SaaS applications include email, customer relationship management, and enterprise resource planning. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 3](https://courses.thorteaches.com/courses/take/cissp/lessons/18591378-virtualization-cloud-and-distributed-computing-part-3). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Software_as_a_service).

Question 51

# Define: Software Encryption

Answer 51

Encryption executed via software algorithms to secure data on general-purpose hardware. ## Footnote Software encryption relies on algorithms and code running on standard hardware to protect data. Although flexible and easily updated, it can be slower than hardware solutions and may be more vulnerable to certain types of software exploits if not properly managed. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Encryption_software).*

Question 52

# Define: Software Exploitation

Answer 52

The process of leveraging software vulnerabilities to compromise or control a system. ## Footnote The act of leveraging software vulnerabilities to gain unauthorized access or control over a system. By exploiting flaws, bugs, or design deficiencies, attackers can bypass security mechanisms, disrupt system functionality, steal sensitive data, or execute arbitrary commands. Effective strategies to counter software exploitation include regular updates and patches, rigorous testing, and security best practices during software development.

Question 53

# Define: Software-Defined Security | (SDS or SDSec)

Answer 53

A security method using software to define and enforce security policies in an organization's network. ## Footnote An approach to security that uses software to define and enforce security policies across an organization's network. It is used to provide centralized, flexible, and scalable security management. Examples of SDS solutions include network security virtualization and software-defined perimeter. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Software-defined_protection).*

Question 54

# Define: Spartan Scytale Cipher

Answer 54

An ancient transposition cipher used by the Spartans for military communication. ## Footnote An ancient encryption tool used by the Spartans where a strip of parchment or leather is wound around a rod of a specific diameter to write a message. When unwound, the letters do not align, and the message appears garbled. The recipient, who has a rod of the same diameter, can read the message by winding the strip around the rod. It's an early example of a transposition cipher. *For more information, view this lecture on [The history of Cryptography - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149612-the-history-of-cryptography-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Scytale).*

Question 55

# Define: Spike

Answer 55

A sharp increase in network traffic or system activity, often indicative of a cyber-attack or system issue. ## Footnote A sudden increase in traffic on a network or system, potentially causing it to crash or slow down. It is used in network analysis and monitoring to detect potential security threats or performance issues. Examples include a spike in web traffic during a cyber-attack or a spike in database queries during peak usage hours. *For more information, view this lecture on [Electricity](https://courses.thorteaches.com/courses/take/cissp/lessons/19149858-electricity). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Voltage_spike).*

Question 56

# Define: SPOOL | (Simultaneous Peripheral Operations Online)

Answer 56

A process where data is stored temporarily to be processed sequentially, such as in print spooling. ## Footnote A computing process where data is temporarily stored to be processed or output sequentially. Commonly associated with print spooling, it allows a computer to receive multiple print jobs at once, which are then queued and sent to the printer or another output device in the order they were received. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/SPOOL).*

Question 57

# Define: Spyware

Answer 57

Malicious software that secretly gathers information about a person or organization without their knowledge. ## Footnote A type of malicious software that covertly collects information about a user or organization without consent, often for personal or financial gain. Spyware can monitor and capture keystrokes, web browsing history, passwords, and other sensitive data. Anti-spyware tools and best practices in cybersecurity hygiene are essential to protect against such invasive software. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Spyware).*

Question 58

# Define: Stack Memory

Answer 58

A type of memory used by the CPU to store temporary data, manage function calls, and control program execution flow. ## Footnote A type of memory used by a computer's central processing unit (CPU) to store and manage data. It is used in computer programming to store temporary data and manage function calls. Examples include storing local variables and function parameters and managing the order in which functions are executed. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Call_stack).*

Question 59

# Define: Stalkerware

Answer 59

Stalkerware is spyware installed on a device—often by someone known to the victim—that tracks location, messages, calls, and browsing activity without user consent. ## Footnote Abuse cases commonly occur in intimate partner violence, letting perpetrators monitor targets’ private lives. Stalkerware marketplaces mislead customers into believing they’re employing legitimate monitoring solutions, but it violates privacy and can be illegal. Security tools can detect or remove these applications, but detection may risk perpetrator retaliation. Awareness, strong device security, and protective legislation are crucial in combating stalkerware. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Stalkerware).*

Question 60

# Define: Standalone System

Answer 60

A self-sufficient system or network that operates independently without relying on external connections. ## Footnote An independent system or network infrastructure that functions without the need for external networks or systems. It's designed to operate autonomously, often for reliability and security, such as an isolated network that does not connect to the internet.

Question 61

# Define: Static Electricity

Answer 61

The accumulation of electrical charge on surfaces, often due to friction or separation. ## Footnote Static Electricity occurs when materials build up excess electrical charge from friction, separation, or induction. This buildup can result in sudden discharges or sparks, posing risks to sensitive electronic components or flammable materials. Controlling static electricity through grounding and other preventative measures is essential in industrial, commercial, and consumer environments to avoid damage and ensure safety. *For more information, view this lecture on [Fire suppression and hot and cold aisles](https://courses.thorteaches.com/courses/take/cissp/lessons/19149912-fire-suppression-and-hot-and-cold-aisles). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Static_electricity).*

Question 62

# Define: Steal the Key

Answer 62

A technique where attackers extract encryption keys to bypass cryptographic protection. ## Footnote Steal the Key describes an attack method in which adversaries retrieve encryption keys from a system via vulnerabilities or physical access. Once in possession of the key, attackers can decrypt data or authenticate maliciously, effectively nullifying encryption. This technique highlights the critical importance of secure key management and robust storage mechanisms in protecting sensitive information. *For more information, view this lecture on [Attacks on our cryptography- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149711-attacks-on-our-cryptography-part-1).*

Question 63

# Define: Stealth Virus

Answer 63

Malicious software that conceals its presence to evade detection and maintain persistence in an infected system. ## Footnote A type of malicious software designed to avoid detection by security software and system monitoring tools. It uses various mechanisms such as obfuscation, encryption, and polymorphic techniques to disguise its presence within the infected system. By concealing itself and its activities, a stealth virus can compromise a system without alerting the user or triggering security protocols. *For more information, view this lecture on [Malware- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18684054-malware-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Stealth_virus).*

Question 64

# Define: Steganography

Answer 64

The practice of hiding secret messages within other, seemingly innocuous data or media to obscure communication. ## Footnote The practice of concealing information within another piece of information. It is often used to embed secret messages in images, audio files, or other data carriers in such a way that no one except the sender and intended recipient even realizes there is a hidden message. In a security context, steganography can be used both for legitimate purposes, such as covert communication, and malicious purposes, such as hiding malware or exfiltrating data. *For more information, view this lecture on [Emanations and Covert Channels](https://courses.thorteaches.com/courses/take/cissp/lessons/18591390-emanations-and-covert-channels). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Steganography).*

Question 65

# Define: Stenography

Answer 65

The art and science of concealing messages within other media. ## Footnote Stenography involves embedding hidden messages into various forms of media such as images, audio files, or text documents. This practice conceals the very existence of the message, offering an additional layer of security by masking communications and protecting sensitive information from unauthorized detection or scrutiny. *For more information, view this lecture on [Emanations and Covert Channels](https://courses.thorteaches.com/courses/take/cissp/lessons/18591390-emanations-and-covert-channels). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Steganography).*

Question 66

# Define: Stream Cipher

Answer 66

An encryption method where plaintext is combined with a pseudorandom cipher stream for secure communication. ## Footnote A method of encryption where each bit or byte of plaintext is combined with a pseudorandom cipher digit stream, typically using a bitwise exclusive-or (XOR) operation. This encryption method provides high speed and hardware efficiency. However, because of the linearity of the XOR operation, it is critical that the same sequence is not used twice, making key management a crucial aspect of secure stream cipher operation. *For more information, view this lecture on [Symmetric encryption- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149624-symmetric-encryption-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Stream_cipher).*

Question 67

# Define: STRIDE Model

Answer 67

A threat modeling framework for identifying and categorizing security threats in application and system design. ## Footnote A threat modeling methodology used to identify potential security risks associated with a system or application. The acronym STRIDE stands for Spoofing, Tampering, Repudiation, Information Disclosure, Denial of Service, and Elevation of Privilege. Each of these represents a class of threat that the model helps to identify, enabling the development of mitigation strategies and increasing the overall resilience of the system. *For more information, view this lecture on [Secure design principles](https://courses.thorteaches.com/courses/take/cissp/lessons/25340659-secure-design-principles). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/STRIDE_(security)).*

Question 68

# Define: Substitution

Answer 68

In cryptography, it's a method where plaintext units are replaced with ciphertext units based on a fixed system. ## Footnote The process of replacing one element with another. In cryptography, substitution is a fundamental method used in various types of ciphers where units of plaintext are replaced with the corresponding units of ciphertext according to a fixed system. The "units" may be single letters, pairs of letters, triplets of letters, mixtures of the above, and so forth. *For more information, view this lecture on [The history of Cryptography - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149612-the-history-of-cryptography-part-1). Or view this lecture on [Introduction to Cryptography- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19121903-introduction-to-cryptography-part-2).*

Question 69

# Define: Substitution Cipher

Answer 69

A cryptographic technique where plaintext elements are systematically replaced with ciphertext elements. ## Footnote A type of cryptographic technique that replaces each letter in a message with a different letter or symbol based on a predetermined key. It is used for secure communication and to protect sensitive information from being intercepted. Examples include the Caesar cipher, the Vigenère cipher, and the Atbash cipher. *For more information, view this lecture on [The history of Cryptography - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149612-the-history-of-cryptography-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Substitution_cipher).*

Question 70

# Define: Surge Suppressor

Answer 70

A device protecting electronic equipment from voltage spikes, ensuring the safety and longevity of the devices. ## Footnote A device that protects electronic equipment from voltage spikes or surges. It is commonly used in homes and businesses to protect computers and other sensitive equipment from damage. Examples include a surge protector strip for a computer, a whole-house surge protector for a home's electrical system, and a surge protector for a commercial server room. *For more information, view this lecture on [Electricity](https://courses.thorteaches.com/courses/take/cissp/lessons/19149858-electricity). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Surge_protector).*

Question 71

# Define: Symmetric Algorithm

Answer 71

An encryption method using the same key for encrypting and decrypting data. ## Footnote A mathematical process used to encrypt and decrypt data. It uses the same secret key for both operations, making it fast and efficient for large amounts of data. Examples include the Advanced Encryption Standard (AES) and the Blowfish algorithm. *For more information, view this lecture on [Symmetric encryption- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149624-symmetric-encryption-part-1). View this lecture on [Symmetric encryption- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19215140-symmetric-encryption-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Symmetric-key_algorithm).*

Question 72

# Define: Symmetric Cipher

Answer 72

A type of encryption using the same key for both encryption and decryption processes. ## Footnote A type of cipher that uses the same key for both encryption and decryption. It is a fundamental type of encryption technique that uses a single key to convert plaintext data into ciphertext, and the same key is used to convert the ciphertext back into the original plaintext. Examples of symmetric ciphers include DES (Data Encryption Standard), AES (Advanced Encryption Standard), and RC4. They are widely used due to their speed and efficiency but require secure key distribution and management. *For more information, view this lecture on [Symmetric encryption- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149624-symmetric-encryption-part-1). View this lecture on [Symmetric encryption- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19215140-symmetric-encryption-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Symmetric-key_algorithm).*

Question 73

# Define: Symmetric Key

Answer 73

A single key used in symmetric encryption for both encrypting and decrypting messages. ## Footnote An encryption method using a single secret key for encrypting and decrypting messages. Both sender and receiver must share and safeguard the key. Symmetric key algorithms are fast and efficient, suitable for encrypting large amounts of data, but require secure key distribution methods to prevent interception. *For more information, view this lecture on [Symmetric encryption- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149624-symmetric-encryption-part-1). View this lecture on [Symmetric encryption- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19215140-symmetric-encryption-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Symmetric-key_algorithm).*

Question 74

# Define: Symmetric Key Encryption

Answer 74

Cryptography using a single key for encryption and decryption, requiring secure key distribution. ## Footnote A form of cryptography that utilizes a single secret key for both encryption and decryption of data. The key is used to convert plaintext data into ciphertext, and the same key is used to convert the ciphertext back into the original plaintext. While this method provides a fast and efficient means of data encryption, securely distributing the key to the intended parties presents a unique challenge, as anyone who possesses the key can decrypt the information. *For more information, view this lecture on [Symmetric encryption- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149624-symmetric-encryption-part-1). View this lecture on [Symmetric encryption- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19215140-symmetric-encryption-part-2).*

Question 75

# Define: Symmetric Multiprocessing | (SMP)

Answer 75

A computer architecture with multiple processors that share a single memory, improving performance and reliability. ## Footnote A computer architecture that enables two or more identical processors to connect and share a single, coherent view of the main memory. SMP systems can process multiple tasks simultaneously, improving performance and reliability. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Symmetric_multiprocessing).*

Question 76

# Define: Synthetic Transactions

Answer 76

Scripts simulating user interactions to monitor system performance and identify potential issues. ## Footnote Scripted actions that simulate user interactions with a system or application. These scripts mimic end-user behavior, such as logging in, navigating through an application, or completing a transaction, to proactively monitor and measure system performance and availability. Synthetic transactions are used in testing environments to identify potential issues before they impact end users, helping to maintain a high level of service availability and security. *For more information, view this lecture on [Domain 6 key concepts](https://courses.thorteaches.com/courses/take/cissp/lessons/19179910-domain-6-key-concepts). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Synthetic_data).*

Question 77

# Define: System Hardening

Answer 77

The process of securing a system by reducing its attack surface through measures like disabling unnecessary services and applying patches. ## Footnote The process of strengthening a computer system's security by reducing its attack surface and vulnerabilities. This can involve disabling unnecessary services, applying security patches, and implementing security controls. Examples of system hardening measures include firewalls, intrusion detection systems, and access controls. *For more information, view this lecture on [Asset tracking and hardware hardening](https://courses.thorteaches.com/courses/take/cissp/lessons/20679155-asset-tracking-and-hardware-hardening). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Hardening_(computing)).*

Question 78

# Define: System High Mode

Answer 78

An operating state where a system functions at maximum security settings typically used in sensitive or classified environments. ## Footnote A state in which a computer system operates at its highest level of security. It is used in military and government organizations to protect sensitive information from unauthorized access. Examples -a classified government database, a military communication network, and a secure online voting system. *For more information, view this lecture on [Security models and concepts- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18591282-security-models-and-concepts-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/System_high_mode).*

Question 79

# Define: System Integrity

Answer 79

The assurance that a system is free from unauthorized access and has not been tampered with or corrupted. ## Footnote The state of a computer system being free from unauthorized access, tampering, or data corruption. This is a key aspect of computer security and is often ensured through the use of encryption, access controls, and backup systems. Examples of system integrity breaches include a hacker accessing sensitive data or a virus corrupting a database. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/System_Integrity).*

Question 80

# Define: Tailgating

Answer 80

Gaining unauthorized access by following someone with legitimate access into a restricted area. ## Footnote The unauthorized access to a restricted area by following someone who has legitimate access. It is a common security risk, especially in physical security environments such as buildings and facilities. Examples include an unauthorized person following an employee into a secured office building, or a visitor following a resident into a gated community. *For more information, view this lecture on [Physical security- Part 4](https://courses.thorteaches.com/courses/take/cissp/lessons/19632100-physical-security-part-4). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Tailgating).*

Question 81

# Define: Take-Grant Model

Answer 81

A formal security model used to understand permission transfer based on take and grant rules. ## Footnote A formal model used to understand how permission and rights can be transferred between subjects in a system based on a set of rules for 'taking' and 'granting' these rights. While not typically deployed in practical systems, it aids in the conceptual understanding of access rights propagation. *For more information, view this lecture on [Security models and concepts- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18591282-security-models-and-concepts-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Take-grant_protection_model).*

Question 82

# Define: Tampering

Answer 82

Illegitimate alteration or damage to systems or devices, a serious security concern. ## Footnote The act of deliberately altering or damaging a system or device without authorization. It is a common security concern, especially in the context of information technology, where tampering can lead to data breaches or loss of integrity. Examples include modifying a computer program to gain unauthorized access to a system or tampering with a security camera to disable its surveillance capabilities. *For more information, view this lecture on [Secure design principles](https://courses.thorteaches.com/courses/take/cissp/lessons/25340659-secure-design-principles). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Tampering).*

Question 83

# Define: Target of Evaluation | (TOE)

Answer 83

A set of components subject to security evaluation, defining the boundaries for testing. ## Footnote A set of software, firmware, and/or hardware components that are the subject of a security evaluation process. The TOE defines the boundaries of the product or system to be tested, including its security functions, interfaces, and implementation. By establishing a TOE, evaluators can systematically identify vulnerabilities, assess risks, and verify the effectiveness of security controls. *For more information, view this lecture on [Security evaluation models](https://courses.thorteaches.com/courses/take/cissp/lessons/18591287-security-evaluation-models). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Security_Target).*

Question 84

# Define: TDE | (Transparent Data Encryption)

Answer 84

TDE automatically encrypts database files at rest, securing stored data without requiring application-level changes or manual encryption routines. ## Footnote Enabling TDE ensures that files and backups remain unreadable if extracted from storage, thwarting offline attacks. Keys typically reside in a secure wallet or key management service. While TDE safeguards data on disk, it doesn’t protect data in transit or memory. Still, it’s a vital layer of defense for compliance and mitigating data breach impacts if physical media is compromised. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Transparent_data_encryption).*

Question 85

# Define: Technical Infrastructure Security

Answer 85

Protection of systems and services that underpin an organization's IT environment against various threats. ## Footnote The protection of the underlying systems and services that support an organization's IT environment. This includes ensuring the security of servers, networks, databases, and other technical assets from threats such as malware, unauthorized access, and data breaches. Key elements of technical infrastructure security include patch management, secure configuration, access control, network security, and monitoring for signs of potential security incidents. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/IT_infrastructure).*

Question 86

# Define: Technology Infrastructure

Answer 86

The collective hardware, software, network resources, and services required for IT operations and management. ## Footnote The composite hardware, software, network resources, and services required for the operation, management, and delivery of IT services and solutions. This infrastructure supports the delivery and processing of information across an organization. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/IT_infrastructure).*

Question 87

# Define: TEMPEST

Answer 87

A set of standards for limiting electromagnetic emissions to prevent eavesdropping on electronic equipment. ## Footnote An unofficial acronym for a set of standards for limiting electric or electromagnetic emissions emanating from electronic equipment. These standards help prevent eavesdropping on sensitive information through the interception of these emissions. Compliance with TEMPEST standards is an aspect of securing classified and sensitive information. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Tempest_(codename)).*

Question 88

# Define: The Ring Model

Answer 88

A security architecture model using layers that protect system components. ## Footnote The Ring Model is a layered security approach where each concentric ring provides a higher level of protection. This design limits access to critical components by enforcing strict boundaries between different security levels, making it more difficult for unauthorized users to compromise the core functions and data of a system. *For more information, view this lecture on [Secure system design concepts](https://courses.thorteaches.com/courses/take/cissp/lessons/18591293-secure-system-design-concepts). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Protection_ring).*

Question 89

# Define: Theft in Virtualization

Answer 89

Unauthorized access or use of virtual resources, posing security risks. ## Footnote Unauthorized access, use, or transference of virtual resources. It can encompass a range of malicious activities, from stealing virtual machines, data, or processing power to misusing virtual networks for illicit activities. This form of theft is a particular concern due to the scalability and dynamism of virtual environments, as illicit activities can be easily replicated or hidden within the complex and often distributed virtual infrastructure.

Question 90

# Define: Thin Client

Answer 90

A lightweight computer that relies on remote servers for processing and storage. ## Footnote A Thin Client is a minimalistic computing device designed to perform basic input and output tasks while depending on a centralized server for processing power, data storage, and application execution. This architecture reduces hardware costs and simplifies maintenance while enhancing security through centralized management. Thin clients are ideal for environments requiring streamlined operations, such as virtual desktop infrastructures or remote work solutions. *For more information, view this lecture on [Secure Communications - Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/29462724-secure-communications-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Thin_client).*

Question 91

# Define: Threat Modeling

Answer 91

Identifying and addressing potential threats in a systematic and prioritized manner. ## Footnote The process of identifying, understanding, and addressing potential threats in a prioritized way. It involves creating a conceptual model of the system or application, including data flow and connectivity, and then identifying assets, threats, and vulnerabilities within this model. The purpose is to mitigate possible security risks during the design phase of a system rather than after deployment. *For more information, view this lecture on [Secure design principles](https://courses.thorteaches.com/courses/take/cissp/lessons/25340659-secure-design-principles). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Threat_model).*

Question 92

# Define: Time Bomb

Answer 92

Malicious code programmed to trigger a harmful event at a specific time or after a period. ## Footnote A malicious piece of code that has been programmed to activate at a specific time or under certain conditions. Unlike a logic bomb, which triggers when a particular event occurs, a time bomb is set to activate on a particular date or after a set amount of time has passed. These are typically used to cause disruption or damage to a system or network, and their delayed activation can make them difficult to detect before they execute. *For more information, view this lecture on [Malware- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18684286-malware-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Time_bomb_(software)).*

Question 93

# Define: Timing Attack

Answer 93

An attack that extracts sensitive information by analyzing the time it takes for a system to respond to inputs. ## Footnote A form of attack where the attacker learns information about the target system by observing the time it takes for the system to respond to inputs. The analysis of the time required to perform cryptographic operations can potentially reveal sensitive data, such as secret keys, especially in poorly implemented cryptographic systems. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Timing_attack).*

Question 94

# Define: TOGAF | (The Open Group Architecture Framework)

Answer 94

A framework for developing and managing enterprise information architecture. ## Footnote A framework that provides a comprehensive approach to the design, planning, implementation, and governance of an enterprise information architecture. It is designed to ensure that the resulting information system is aligned with business needs and is cost-effective, reliable, and scalable. The TOGAF standard includes a set of guiding principles, methods, and a supporting toolset for designing an enterprise architecture. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/The_Open_Group_Architecture_Framework).*

Question 95

# Define: Tokenization

Answer 95

Converting sensitive data into non-sensitive equivalents, or tokens, to secure information. ## Footnote The process of converting sensitive data into a series of random, meaningless characters or tokens. It is used to protect data during transmission and storage. Examples -using tokenization to protect credit card information during online transactions and using tokenization to protect sensitive medical records in a healthcare database. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Tokenization_(data_security)).*

Question 96

# Define: TPM | (Trusted Platform Module)

Answer 96

A standard for a hardware-based secure cryptoprocessor that safeguards sensitive information. ## Footnote TPM is a secure crypto-processor that is designed to carry out cryptographic operations. It is a hardware-based security feature that provides a secure environment for storing cryptographic keys, passwords, and digital certificates. It is used in computers, laptops, and other devices to securely store and manage sensitive information. Examples include using TPM for secure booting, user authentication, and data encryption. *For more information, view this lecture on [Hardware architecture- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/45831595-hardware-architecture-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Trusted_Platform_Module).*

Question 97

# Define: Transport Encryption

Answer 97

Encryption of data in transit between systems or over networks to prevent unauthorized access and maintain confidentiality. ## Footnote A technique used to protect data in transit between systems or across networks, including the internet. It involves encrypting the data before transmission and then decrypting it upon arrival at its destination. Transport encryption is crucial for preventing unauthorized access to data as it travels across networks, guarding against interception, and preserving data integrity and confidentiality.

Question 98

# Define: Transposition and Permutation

Answer 98

Cryptographic techniques involving the rearrangement of characters or bits in a message to encrypt data. ## Footnote In cryptography, transposition refers to rearranging the characters in a message, while permutation involves rearranging bits, bytes, or other parts of the message according to a specific system or rule. Both are techniques used to obscure the content of a message. *For more information, view this lecture on [Introduction to Cryptography- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19121903-introduction-to-cryptography-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Transposition_cipher).*

Question 99

# Define: Transposition Cipher

Answer 99

A transposition cipher rearranges the letters of the plaintext according to a systematic pattern, changing their positions without altering the actual characters used. ## Footnote Unlike substitution ciphers that replace letters, transposition simply reshuffles them. Classic examples include the rail fence cipher, where text is written in a zigzag pattern, then read row by row. Security stems from the difficulty of restoring the correct ordering. However, frequency analysis may assist skilled cryptanalysts. Modern cryptography surpasses transposition ciphers, but they illuminate foundational encryption principles. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Transposition_cipher).*

Question 100

# Define: Trapdoor Function

Answer 100

A mathematical function that is easy to compute in one direction but difficult to reverse without specific knowledge. ## Footnote A function that is easy to compute in one direction but believed to be difficult to compute in the opposite direction without special information, called a 'trapdoor'. These functions are essential in the construction of encryption algorithms, particularly public-key cryptosystems. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Trapdoor_function).*

Question 101

# Define: Trojans

Answer 101

Trojans are malicious software disguised as legitimate applications, tricking users into installation and opening a hidden backdoor or executing harmful payloads. ## Footnote Commonly delivered via email attachments, fake software downloads, or rogue links, Trojans establish attacker access to compromised systems. Attackers can steal data, install ransomware, or expand botnets. Defending against Trojans requires applying security patches, scanning for suspicious files, and training users to identify social engineering tactics. Vigilance and layered protections help detect and remove Trojan infections before serious damage occurs. *For more information, view this lecture on [Malware- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18684286-malware-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Trojan_horse_(computing)).*

Question 102

# Define: Trust But Verify

Answer 102

A principle emphasizing the importance of trusting entities while also ensuring their actions are validated. ## Footnote A principle that emphasizes the importance of establishing confidence in entities while also validating their actions. It suggests that while one may trust an entity, their actions and activities should be independently checked for accuracy, reliability, and integrity, maintaining a balance between trust and security control. *For more information, view this lecture on [Secure design principles.](https://courses.thorteaches.com/courses/take/cissp/lessons/25340659-secure-design-principles). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Web_of_trust).*

Question 103

# Define: Trust Model

Answer 103

A framework outlining how trust is established and managed within a network or system. ## Footnote This outlines the approach to trust relationships within a network or between systems. It defines how trust is established, who or what can be trusted, and the extent to which trust is granted. Models can vary from simple (one trusted entity) to complex (hierarchical or web-of-trust models). *For more information, view this lecture on [Secure design principles.](https://courses.thorteaches.com/courses/take/cissp/lessons/25340659-secure-design-principles). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Web_of_trust).*

Question 104

# Define: Trusted Channel

Answer 104

A secure communication pathway that ensures data transmitted between parties is confidential and secure. ## Footnote A trusted channel is a secure communication pathway that ensures data is transmitted confidentially and securely between parties, preventing unauthorized access and ensuring that the data has not been altered or intercepted during transit. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Secure_channel).*

Question 105

# Define: Trusted Computer System

Answer 105

A system designed to enforce a security policy, offering a certain level of assurance in its operation. ## Footnote A system that is relied upon to enforce a specific security policy. It has been designed and configured to provide a certain level of assurance for maintaining the confidentiality, integrity, and availability of the information it processes. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Trusted_system).*

Question 106

# Define: Trusted Computer System Evaluation Criteria | (TCSEC) (Aka Orange Book)

Answer 106

A DoD standard for assessing the security of computer systems. ## Footnote A United States Government Department of Defense standard that sets basic requirements for assessing the effectiveness of security controls built into a computer system. It provides a metric to evaluate and measure the security properties of a computer system. *For more information, view this lecture on [Security evaluation models.](https://courses.thorteaches.com/courses/take/cissp/lessons/18591287-security-evaluation-models). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Trusted_Computer_System_Evaluation_Criteria).*

Question 107

# Define: Trusted Computing Base | (TCB)

Answer 107

Components critical to a system's security, ensuring it adheres to security policies and operates securely. ## Footnote The collection of all hardware, firmware, and software components within a system that are critical to its security. The TCB provides a foundation of trust for a system by ensuring that enforced security policies are adhered to and that the system operates in a predictable and secure manner. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Trusted_Computing_Base).*

Question 108

# Define: Trusted Path

Answer 108

A secure communication link ensuring a user's direct interaction with the legitimate system rather than an imposter. ## Footnote A secure route or channel between a user and the system, ensuring that the user is directly communicating with the legitimate system and not an imposter. This route is protected against interception, modification, or mimicry by unauthorized or malicious entities.

Question 109

# Define: Trusted Process

Answer 109

A verified procedure with elevated access to perform sensitive operations, crucial for system integrity. ## Footnote A procedure that has been vetted and authorized to access resources and information beyond the restrictions imposed on most processes. It has the necessary permissions to perform sensitive operations, making it crucial that its integrity and security are maintained.

Question 110

# Define: Trusted System

Answer 110

A system with robust security measures ensuring reliable enforcement of security policies. ## Footnote A system that has been thoroughly reviewed, tested, and proven to reliably enforce security policies. The trust in these systems comes from their proven ability to protect the confidentiality, integrity, and availability of the data they handle, even in the presence of threats.

Question 111

# Define: Turnstile

Answer 111

A physical barrier controlling individual entry, often integrated with authentication systems for security. ## Footnote A form of physical access control, turnstiles regulate individual entry to secure areas one person at a time, often requiring authentication like badges, tickets, or biometrics. They're used in various settings, from public transit to high-security buildings, to prevent unauthorized access and manage pedestrian traffic flow. *For more information, view this lecture on [Physical security- Part 4.](https://courses.thorteaches.com/courses/take/cissp/lessons/19632100-physical-security-part-4). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Turnstile).*

Question 112

# Define: Twofish

Answer 112

A symmetric key block cipher praised for security and performance, a finalist in the AES selection process. ## Footnote A symmetric key block cipher known for its simplicity and speed. It was one of the five finalists in the Advanced Encryption Standard (AES) contest, where it was praised for its high security, good performance, and ease of implementation. *For more information, view this lecture on [Symmetric encryption- Part 2.](https://courses.thorteaches.com/courses/take/cissp/lessons/19215140-symmetric-encryption-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Twofish).*

Question 113

# Define: Two-Person Control

Answer 113

A security protocol requiring two individuals to perform sensitive tasks, preventing unauthorized or fraudulent actions. ## Footnote A security concept used to maintain high levels of safety and integrity by ensuring that two or more individuals are required to perform certain sensitive or high-risk tasks. This technique prevents a single individual from having sole authority or access and is often applied to prevent fraudulent activities or unauthorized actions. *For more information, view this lecture on [Physical security- Part 3.](https://courses.thorteaches.com/courses/take/cissp/lessons/19632079-physical-security-part-3). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Two-man_rule).*

Question 114

# Define: Type 1 Hypervisor

Answer 114

A hypervisor running directly on host hardware, isolating operating systems for security and efficiency. ## Footnote A type of hypervisor that runs directly on a physical host machine's hardware, allowing multiple operating systems to be run on the same physical server. It is used in server virtualization and cloud computing environments. Examples include VMware ESXi and Microsoft Hyper-V. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Hypervisor#Type-1_(native,_bare-metal)_hypervisors).*

Question 115

# Define: Type 2 Hypervisor

Answer 115

A hypervisor that runs within a host operating system, allowing for multiple virtual environments. ## Footnote A type of hypervisor that runs within a host operating system, allowing multiple virtual machines to be run on the same physical host. It is used in desktop virtualization and personal cloud computing environments. Examples include VMware Workstation and Oracle VirtualBox. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Hypervisor#Type-2_(hosted)_hypervisors).*

Question 116

# Define: UAVS | (Unmanned Aerial Vehicles)

Answer 116

UAVs, often known as drones, are aircraft piloted remotely or autonomously, used for surveillance, delivery, photography, and various commercial or military operations. ## Footnote They vary in size and range, equipped with onboard cameras or sensors. Advanced models can navigate with GPS, computer vision, or AI-based guidance. Security concerns include unauthorized surveillance, hacking vulnerabilities, and potential collisions. Regulatory frameworks manage airspace usage, requiring operational licenses or restricted flight zones. Despite risks, UAVs revolutionize logistics, research, and emergency response with agility and cost-effectiveness. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Unmanned_aerial_vehicle).*

Question 117

# Define: UEFI Firmware | (Unified Extensible Firmware Interface)

Answer 117

UEFI is a modern replacement for the traditional BIOS, providing a modular and extensible interface to initialize hardware and boot operating systems securely. ## Footnote UEFI supports features like Secure Boot, large disk partitions, and faster startup times. Its driver-based architecture allows advanced hardware management and updatable firmware. While improving flexibility, it also introduces potential attack surfaces. Vendors mitigate risks by cryptographically signing firmware updates and limiting privilege. UEFI fosters robust system initialization routines, offering performance gains and stronger security. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Unified_Extensible_Firmware_Interface).*

Question 118

# Define: Ultrasonic Sensors

Answer 118

Ultrasonic sensors emit high-frequency sound waves to measure distance or detect motion by timing reflections, used in automation, robotics, and security systems. ## Footnote Often seen in parking assist systems, ultrasonic sensors can also trigger alarms if someone crosses a set threshold. They operate on short-range signals, unaffected by visual obstructions, though certain environments or materials absorb or scatter sound. Proper calibration avoids false positives. When integrated with broader security controls, ultrasonic sensors enhance perimeter or device sensing capabilities. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Ultrasonic_sensor).*

Question 119

# Define: Uninterruptible Power Supply | (UPS)

Answer 119

A backup power system providing temporary electricity to prevent data loss during power outages. ## Footnote A device that provides a consistent flow of electricity to connected systems for a short period of time when the primary power source is lost. In an environment where system availability is critical, a UPS can prevent system downtime, loss of data, or hardware damage due to power interruptions. *For more information, view this lecture on [Electricity.](https://courses.thorteaches.com/courses/take/cissp/lessons/19149858-electricity). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Uninterruptible_power_supply).*

Question 120

# Define: UNIX

Answer 120

A secure and stable operating system family used for multitasking and multi-user applications, like servers. ## Footnote A family of operating systems that are widely used in servers and other large-scale computing systems. It is known for its security and stability and its ability to handle multiple users and processes simultaneously. Examples include Linux, Solaris, and macOS. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Unix).*

Question 121

# Define: Updating

Answer 121

The process of installing software patches, enhancements, or fixes to improve system security and functionality. ## Footnote The process of applying patches, bug fixes, or enhancements to a system or software. Regular updates are crucial for maintaining system security as they often contain fixes for known vulnerabilities that could otherwise be exploited. The updating process should be managed carefully to minimize the potential for introducing new vulnerabilities or disrupting system functionality. *For more information, view this lecture on [Change management.](https://courses.thorteaches.com/courses/take/cissp/lessons/19180365-change-management).*

Question 122

# Define: Uptime Institute

Answer 122

An organization specializing in the certification and standardization of data center reliability and performance. ## Footnote An organization that provides standards and certifications for data center reliability and efficiency. Their guidelines focus on both physical and logical components of data center operations, and adherence to their standards can significantly enhance the reliability and security of data center services. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Uptime_Institute).*

Question 123

# Define: USB | (Universal Serial Bus)

Answer 123

A connection interface for transferring data and connecting various devices with potential security implications. ## Footnote A standard type of connection interface used for transferring data and connecting devices. USBs can pose a security risk due to their ability to carry and transmit data and malware. Proper management, including limiting usage, disabling unnecessary ports, and scanning for malware, can mitigate these risks. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/USB).*

Question 124

# Define: User Mode

Answer 124

A restricted operating state limiting software application access to critical system resources. ## Footnote An operating state in modern computer systems that limits the access rights of software applications, preventing them from directly interacting with hardware or system resources. This mode maintains system stability and security by restricting application access to sensitive areas of the operating system. *For more information, view this lecture on [Secure system design concepts.](https://courses.thorteaches.com/courses/take/cissp/lessons/18591293-secure-system-design-concepts). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Privilege_level).*

Question 125

# Define: Variant

Answer 125

A form or version of something slightly different from the original, like altered versions of malware. ## Footnote A version or form of something that is slightly different from the original. In the context of malware, for instance, a variant refers to a version of the malicious software that has been slightly altered from its original form, often to avoid detection by security measures or to adapt to different environments.

Question 126

# Define: Vendor Lock-In | (Cloud Computing)

Answer 126

A situation where a customer becomes dependent on a single cloud provider's infrastructure. ## Footnote A situation where a customer using cloud services becomes dependent on a single cloud provider's infrastructure and tools, making it difficult or costly to migrate to another service. This can be due to proprietary technologies, custom APIs, or data transfer costs. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Vendor_lock-in).*

Question 127

# Define: Vendor Lock-Out | (Cloud Computing)

Answer 127

A strategy where a cloud provider excludes competitors from integrating with its platform. ## Footnote A strategy where a cloud service provider may exclude competitors' services or products from integrating with its own platform, enforcing a form of ecosystem control that can limit customer choice and interoperability between different cloud services. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Vendor_lock-in).*

Question 128

# Define: Vertical Scalability

Answer 128

Vertical scalability, also known as scaling up, involves increasing the capacity of a single system (e.g., adding CPU, RAM) to handle higher workloads. ## Footnote Compared to horizontal scaling, it doesn’t require coordinating multiple servers. While simpler to implement initially, hardware limitations and potential single points of failure can hamper long-term growth. Vertical scaling might mean upgrading to more powerful machines or leveraging virtualization for resource management. Balancing cost, downtime, and performance makes vertical scalability an option, though massive workloads may benefit from combined or horizontal strategies. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Scalability).*

Question 129

# Define: Video Monitoring or Video Surveillance

Answer 129

The use of cameras and other devices to observe and record activities for security purposes. ## Footnote The use of cameras and other visual recording devices to monitor and record activities within a specific area. It is used for security purposes, to identify potential threats or incidents, and to provide evidence of criminal activity. Examples include CCTV cameras in a shopping mall or security cameras in a parking lot. *For more information, view this lecture on [Physical security- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19149796-physical-security-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Closed-circuit_television).*

Question 130

# Define: Vigènere Cipher

Answer 130

The Vigènere cipher is a classic polyalphabetic substitution cipher that shifts letters by different amounts based on a repeating keyword, obscuring frequency patterns. ## Footnote Users align plaintext and key characters to determine each ciphertext character. Although stronger than simple Caesar ciphers, it’s vulnerable to Kasiski examination or frequency analysis if the key length is known. Historically popular, it was once deemed “le chiffrage indéchiffrable” (the indecipherable encryption). Though outdated for modern applications, the Vigènere cipher remains an instructive example of cryptographic evolution. *For more information, view this lecture on [The history of Cryptography - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149612-the-history-of-cryptography-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Vigen%C3%A8re_cipher).*

Question 131

# Define: Virtual Machine Escape

Answer 131

A breach where an attacker escapes a VM's isolation to interact with the host system. ## Footnote The instance where an attacker successfully breaches a virtual machine's confines to interact with the host system. By exploiting vulnerabilities within the virtual machine environment, attackers may breach the separation boundary, leading to the compromise of other virtual machines hosted on the same physical system. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtual_machine_escape).*

Question 132

# Define: Virtual Machines | (VMs)

Answer 132

Simulations of physical computers that run independently on a host machine, providing security through isolation. ## Footnote Software-based representations of physical computers, capable of executing applications and processes like their physical counterparts. VMs operate on a physical host machine, allowing multiple virtual machines to operate simultaneously and independently, which can enhance resource efficiency, scalability, and isolation of processes, potentially enhancing overall security. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtual_machine).*

Question 133

# Define: Virtual Memory

Answer 133

A method that uses hardware and software to allow a computer to compensate for physical memory shortages. ## Footnote A memory management technique that provides an idealized abstraction of the storage resources that are actually available on a system. It creates an illusion to users of a very large (main) memory by using the hard disk as an extension of the RAM, enhancing system performance and isolation of processes. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtual_memory).*

Question 134

# Define: Virtual Private Cloud | (VPC)

Answer 134

An isolated environment within a public cloud that offers enhanced privacy and control for network resources. ## Footnote A virtual network that provides a private and isolated environment in a public cloud infrastructure. It offers an organization control over network configurations, including IP address ranges, subnets, route tables, and network gateways, enabling it to launch resources in a defined virtual network, enhancing the organization's data privacy and security. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Amazon_Virtual_Private_Cloud).*

Question 135

# Define: Virtualization

Answer 135

The creation of virtual versions of hardware, software, or networks to optimize resource utilization and security. ## Footnote The process of creating a software-based (or virtual) representation of something rather than a physical one. It can apply to applications, servers, storage, and networks and is the backbone of cloud computing, enabling more efficient utilization of physical computer hardware and offering flexibility, scalability, and potential cost savings. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtualization).*

Question 136

# Define: Virus

Answer 136

Malicious software that replicates by inserting its code into other programs, potentially causing harm and security breaches. ## Footnote A type of malicious software that, when executed, replicates itself by modifying other computer programs and inserting its own code. Viruses can have harmful side effects, causing harm to system software by corrupting or destroying data, slowing down system performance, or giving attackers access to system resources. *For more information, view this lecture on [Malware- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18684054-malware-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Computer_virus).*

Question 137

# Define: Virus Signature File

Answer 137

A database used by antivirus software to identify known viruses based on their unique patterns. ## Footnote A file that contains the definitions and characteristics of known viruses, used by antivirus software to identify and block viruses. Virus signature files are used to protect computers and networks from virus attacks. Examples of virus signature files include virus definition files and virus pattern files. *For more information, view this lecture on [Malware- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18684286-malware-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Computer_virus#Read_request_intercepts).*

Question 138

# Define: Visual, Agile, and Simple Threat Modeling | (VAST)

Answer 138

A threat modeling approach that simplifies the analysis of security risks in system design. ## Footnote An approach to threat modeling that emphasizes simplicity, collaboration, and integration with Agile development processes. VAST promotes visualization of threats and vulnerabilities in system design, which enables team-wide understanding and continuous iteration of threat models alongside system development.

Question 139

# Define: VM Escapes | (Virtual Machine)

Answer 139

A security breach where an attacker gains unauthorized access to the host system from within a virtual machine. ## Footnote A security breach in which the attacker breaks out of a virtual machine and interacts directly with the host operating system. This can be a serious issue as it can give the attacker access to the host environment and other virtual machines running on the same host, potentially compromising the entire system. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtual_machine_escape).*

Question 140

# Define: VM Virtualbox

Answer 140

An open-source virtualization software enabling multiple operating systems to run on one hardware platform. ## Footnote VM VirtualBox is a free virtualization tool that allows users to install and run multiple guest operating systems on a single host machine. It provides a secure, isolated environment ideal for testing, development, and running legacy applications, while offering extensive configuration options and cross-platform support for diverse computing environments. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/VirtualBox).*

Question 141

# Define: VMI | (Virtual Machine Introspection)

Answer 141

A security technique that monitors virtual machine states from outside to detect unusual behavior. ## Footnote A technique used to monitor the runtime state of a system-level virtual machine. From outside the virtual machine, it inspects the machine's operations, such as memory and disk activity, to spot any unusual or suspicious behavior. This method provides a way of maintaining a high level of security and integrity within the operational environment. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtual_machine_introspection).*

Question 142

# Define: VMs | (Virtual Machines)

Answer 142

Simulated computing systems that run on physical hardware, providing efficiency and isolation. ## Footnote Emulations of computer systems. They mimic actual computers by replicating the same functionality, enabling them to run applications and programs like a physical machine. This approach allows for more efficient resource utilization by allowing multiple virtual machines to run simultaneously on a single physical host. *For more information, view this lecture on [Virtualization, Cloud, and Distributed Computing - Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/18591372-virtualization-cloud-and-distributed-computing-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Virtual_machine).*

Question 143

# Define: Weak Key Attack

Answer 143

An exploit targeting cryptographic algorithms that exhibit vulnerabilities when certain 'weak' keys are used. ## Footnote An attack on cryptographic algorithms where specific keys, known as weak keys, lead to patterns or simplifications in the encrypted data. This can make decryption without the intended key more feasible and hence compromise the effectiveness of the cryptographic protection. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Weak_key).*

Question 144

# Define: Web of Trust

Answer 144

A decentralized trust model based on mutual endorsements among users. ## Footnote The Web of Trust is a security model wherein individuals validate each other's identities through mutual endorsements rather than relying on a central certificate authority. Commonly used in PGP systems, it builds a network of trust where users decide on whom to trust based on personal connections and recommendations. This approach promotes decentralized verification, allowing for flexible and community-driven security validations. *For more information, view this lecture on [IPSec and PGP](https://courses.thorteaches.com/courses/take/cissp/lessons/19149746-ipsec-and-pgp). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Web_of_trust).*

Question 145

# Define: Wet Pipe

Answer 145

A fire sprinkler system in which the pipes always contain pressurized water. ## Footnote A Wet Pipe system is a type of automatic fire suppression setup where water continuously fills the pipes, ensuring immediate discharge upon activation by a sprinkler head. Widely used in buildings, these systems offer rapid response to fires. However, their design requires careful installation to prevent accidental discharge and to maintain system integrity under various environmental conditions. *For more information, view this lecture on [Fire suppression- Part 1](https://courses.thorteaches.com/courses/take/cissp/lessons/19149928-fire-suppression-part-1). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Fire_sprinkler_system#Wet_pipe).*

Question 146

# Define: Whole-Instance Encryption

Answer 146

Encrypting an entire virtual machine or cloud instance to protect all contained data and applications. ## Footnote The process of encrypting an entire virtual machine or cloud instance, including all data and applications. It is used in the field of cloud computing to protect data and ensure compliance with regulations. For example, encrypting a virtual machine running on a public cloud platform or encrypting a database in a cloud environment.

Question 147

# Define: Wildcard Certificates

Answer 147

Digital certificates that secure all subdomains under a single domain. ## Footnote Wildcard certificates allow one certificate to secure a primary domain and all its subdomains, streamlining management and reducing costs. They are widely used in dynamic web environments where multiple subdomains require uniform security. While providing operational efficiency, careful management is necessary because any compromise of the certificate can potentially affect all associated subdomains. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Wildcard_certificate).*

Question 148

# Define: Windows

Answer 148

Windows is Microsoft’s widely used operating system offering a graphical interface, extensive application support, and enterprise management capabilities for desktops, servers, and embedded devices. ## Footnote Evolving from command-line DOS roots, Windows includes features like Active Directory, Group Policy, and integrated security tools. Regular updates patch vulnerabilities and expand functionality. Although it’s a popular target for malware, security can be strengthened through best practices—such as enabling antivirus, applying patches, and configuring firewalls. Windows powers a significant share of global computing across personal, business, and government environments. *For more information, view this lecture on [Secure operating systems and software architecture](https://courses.thorteaches.com/courses/take/cissp/lessons/18591315-secure-operating-systems-and-software-architecture). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Microsoft_Windows).*

Question 149

# Define: Windows Group Policy

Answer 149

Windows group policy is a centralized feature of Active Directory that defines rules and settings for user accounts and computers across a Windows domain. ## Footnote Administrators enforce security guidelines, deploy software, and manage system configurations without manually adjusting individual PCs. Configurations span from password complexity to desktop restrictions, enabling uniform compliance and simpler administration. Group Policy supports hierarchical application, from domain-wide down to specific organizational units. Properly designed policies reduce misconfigurations, promote standardization, and align with business or regulatory requirements. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Group_Policy).*

Question 150

# Define: Windows Registry

Answer 150

A hierarchical database on Windows operating systems storing low-level settings for applications and the system. ## Footnote A database of system settings and configurations in the Microsoft Windows operating system. It is used to store information such as software installation paths, user preferences, and hardware settings. Examples of registry keys include the HKEY_LOCAL_MACHINE and HKEY_CURRENT_USER keys. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Windows_Registry).*

Question 151

# Define: Work Factor

Answer 151

The estimated effort required to break a cryptographic system, a measure of its security. ## Footnote A measure of the effort required to perform a certain task or to break a certain system. It is used in cryptography to determine the security of a cryptographic system. Examples of work factors include the time required to brute-force a password or the amount of memory required to perform a certain cryptographic operation. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Encryption#Limitations).*

Question 152

# Define: Workstation

Answer 152

A network-connected computer used for professional tasks, requiring security measures to protect network access and data. ## Footnote A computer that is connected to a network and is used for tasks like data processing, data analysis, and other professional applications. Workstations can be individually targeted in network attacks due to their access to valuable data or network resources. Thus, security measures such as antivirus software, firewalls, and user access controls are crucial to protect the data and network resources accessible from a workstation. *For more information, visit this [Wikipedia page](https://en.wikipedia.org/wiki/Workstation).*

Question 153

# Define: Worm

Answer 153

Self-replicating malware that spreads across networks, exploiting vulnerabilities to infect systems without user interaction. ## Footnote A type of malware that self-replicates to spread to other computers. Unlike viruses, worms do not need to attach themselves to a host program. They often exploit network vulnerabilities to infect systems and can cause widespread damage without user intervention. *For more information, view this lecture on [Malware- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18684286-malware-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Computer_worm).*

Question 154

# Define: XML Injection

Answer 154

An attack that inserts malicious XML input into a system, potentially compromising XML processing applications. ## Footnote An attack where malicious XML code is inserted into a system, exploiting insecure processing of XML input by an application. This can affect the logic of XML parsers, leading to unauthorized access, data exposure, or service disruption. It's distinct from other injection attacks by specifically targeting XML parser vulnerabilities. *For more information, view this lecture on [Web architecture and attacks](https://courses.thorteaches.com/courses/take/cissp/lessons/19148725-web-architecture-and-attacks). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Code_injection#XML_injection).*

Question 155

# Define: XOR

Answer 155

A logical operation used in many computing and cryptography applications for data manipulation and encryption. ## Footnote A logical operation that outputs true only when one of the inputs is true. It is commonly used in computer science and cryptography to perform logical operations and encrypt data. Examples include binary XOR, bitwise XOR, and Boolean XOR. *For more information, view this lecture on [Introduction to Cryptography- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/19121903-introduction-to-cryptography-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Exclusive_or).*

Question 156

# Define: Zachman Framework

Answer 156

An enterprise architecture framework categorizing and organizing architectural components for planning and design. ## Footnote A system for categorizing and organizing the components of an enterprise architecture. It is used by organizations to help plan, design, and implement complex information systems and to ensure alignment with business goals and strategies. Examples of Zachman framework components include data, function, network, people, and time. *For more information, view this lecture on [Security models and concepts- Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/18591282-security-models-and-concepts-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Zachman_Framework).*

Question 157

# Define: Zero Client

Answer 157

An endpoint device with no local processing, entirely dependent on a remote system. ## Footnote A Zero Client is an ultra-simplified computing device that has no onboard storage, operating system, or data processing capabilities. It connects directly to a remote desktop or virtualized environment, where all processing is performed on a server. This design enhances security and reduces maintenance efforts, making zero clients suitable for high-control and resource-optimized deployments. *For more information, view this lecture on [Secure Communications - Part 2](https://courses.thorteaches.com/courses/take/cissp/lessons/29462724-secure-communications-part-2). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Zero_client).*

Question 158

# Define: Zero-Knowledge Proof

Answer 158

A cryptographic method allowing one party to prove knowledge of information without revealing the information. ## Footnote A mathematical proof that allows one party to prove to another party that they know a certain piece of information without revealing the information itself. It is used in cryptography and secure communication protocols to verify the authenticity of a user or device without exposing sensitive information. Examples of zero-knowledge proofs include the Schnorr signature algorithm and the Fiat-Shamir heuristic. *Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Zero-knowledge_proof).*

Question 159

# Define: Zero-Trust Architecture

Answer 159

A security model that does not automatically trust any user or device, requiring stringent verification for access. ## Footnote A security model that assumes no user or device can be trusted by default, regardless of its location (inside or outside the network) or whether it has previously been verified. Instead, every request for access to resources must be authenticated and authorized. This approach minimizes the potential for unauthorized access and reduces the attack surface by limiting access to only what is needed for a specific task, even if a user's credentials or device has been compromised. *For more information, view this lecture on [Secure Access Service Edge](https://courses.thorteaches.com/courses/take/cissp/lessons/54398562-new-2024-sase-secure-access-service-edge). Or visit this [Wikipedia page](https://en.wikipedia.org/wiki/Zero_trust_security).*