How to Easily Pass the ISC CISSP Exam: Expert Advice

Asymmetric Card Authentication Key (CAK) challenge-response is an effective control in preventing electronic cloning of RFID based access cards. RFID based access cards are contactless cards that use radio frequency identification (RFID) technology to communicate with a reader and grant access to a physical or logical resource. RFID based access cards are vulnerable to electronic cloning, which is the process of copying the data and identity of a legitimate card to a counterfeit card, and using it to impersonate the original cardholder and gain unauthorized access. Asymmetric CAK challenge-response is a cryptographic technique that prevents electronic cloning by using public key cryptography and digital signatures to verify the authenticity and integrity of the card and the reader. Asymmetric CAK challenge-response works as follows:

• The card and the reader each have a pair of public and private keys, and the public keys are exchanged and stored in advance.
• When the card is presented to the reader, the reader generates a random number (nonce) and sends it to the card.
• The card signs the nonce with its private key and sends the signature back to the reader.
• The reader verifies the signature with the card’s public key and grants access if the verification is successful.
• The card also verifies the reader’s identity by requesting its signature on the nonce and checking it with the reader’s public key.

Asymmetric CAK challenge-response prevents electronic cloning because the private keys of the card and the reader are never transmitted or exposed, and the signatures are unique and non-reusable for each transaction. Therefore, a cloned card cannot produce a valid signature without knowing the private key of the original card, and a rogue reader cannot impersonate a legitimate reader without knowing its private key.

The other options are not as effective as asymmetric CAK challenge-response in preventing electronic cloning of RFID based access cards. Personal Identity Verification (PIV) is a standard for federal employees and contractors to use smart cards for physical and logical access, but it does not specify the cryptographic technique for RFID based access cards. Cardholder Unique Identifier (CHUID) authentication is a technique that uses a unique number and a digital certificate to identify the card and the cardholder, but it does not prevent replay attacks or verify the reader’s identity. Physical Access Control System (PACS) repeated attempt detection is a technique that monitors and alerts on multiple failed or suspicious attempts to access a resource, but it does not prevent the cloning of the card or the impersonation of the reader.

 When developing an information security management system (ISMS), an initial consideration is to understand the value of the information assets that the organization owns or processes. An information asset is any data, information, or knowledge that has value to the organization and supports its mission, objectives, and operations. Understanding the value of the information assets helps to determine the appropriate level of protection and investment for them, as well as the potential impact and consequences of losing, compromising, or disclosing them. Understanding the value of the information assets also helps to identify the stakeholders, owners, and custodians of the information assets, and their roles and responsibilities in the ISMS.

The other options are not initial considerations, but rather subsequent or concurrent considerations when developing an ISMS. Identifying the contractual security obligations that apply to the organizations is a consideration that depends on the nature, scope, and context of the information assets, as well as the relationships and agreements with the external parties. Identifying the level of residual risk that is tolerable to management is a consideration that depends on the risk appetite and tolerance of the organization, as well as the risk assessment and analysis of the information assets. Identifying relevant legislative and regulatory compliance requirements is a consideration that depends on the legal and ethical obligations and expectations of the organization, as well as the jurisdiction and industry of the information assets.

 When assigning ownership of an asset to a department, the most important factor is to ensure individual accountability for the asset. Individual accountability means that each person who has access to or uses the asset is responsible for its protection and proper handling. Individual accountability also implies that each person who causes or contributes to a security breach or incident involving the asset can be identified and held liable. Individual accountability can be achieved by implementing security controls such as authentication, authorization, auditing, and logging.

The other options are not as important as ensuring individual accountability, as they do not directly address the security risks associated with the asset. The department should report to the business owner is a management issue, not a security issue. Ownership of the asset should be periodically reviewed is a good practice, but it does not prevent misuse or abuse of the asset. All members should be trained on their responsibilities is a preventive measure, but it does not guarantee compliance or enforcement of the responsibilities.

In a data classification scheme, the data is owned by the business managers. Business managers are the persons or entities that have the authority and accountability for the creation, collection, processing, and disposal of a set of data. Business managers are also responsible for defining the purpose, value, and classification of the data, as well as the security requirements and controls for the data. Business managers should be able to determine the impact the information has on the mission of the organization, which means assessing the potential consequences of losing, compromising, or disclosing the data. The impact of the information on the mission of the organization is one of the main criteria for data classification, which helps to establish the appropriate level of protection and handling for the data.

The other options are not the data owners in a data classification scheme, but rather the other roles or functions related to data management. System security managers are the persons or entities that oversee the security of the information systems and networks that store, process, and transmit the data. They are responsible for implementing and maintaining the technical and physical security of the data, as well as monitoring and auditing the security performance and incidents. Information Technology (IT) managers are the persons or entities that manage the IT resources and services that support the business processes and functions that use the data. They are responsible for ensuring the availability, reliability, and scalability of the IT infrastructure and applications, as well as providing technical support and guidance to the users and stakeholders. End users are the persons or entities that access and use the data for their legitimate purposes and needs. They are responsible for complying with the security policies and procedures for the data, as well as reporting any security issues or violations.

The passage of time is one of the factors that affects the classification of data. Data classification is the process of assigning a level of sensitivity or criticality to data based on its value, impact, and legal requirements. Data classification helps to determine the appropriate security controls and handling procedures for the data. However, data classification is not static, but dynamic, meaning that it can change over time depending on various factors. One of these factors is the passage of time, which can affect the relevance, usefulness, or sensitivity of the data. For example, data that is classified as confidential or secret at one point in time may become obsolete, outdated, or declassified at a later point in time, and thus require a lower level of protection. Conversely, data that is classified as public or unclassified at one point in time may become more valuable, sensitive, or regulated at a later point in time, and thus require a higher level of protection. Therefore, data classification should be reviewed and updated periodically to reflect the changes in the data over time.

The other options are not factors that affect the classification of data, but rather the outcomes or components of data classification. Assigned security label is the result of data classification, which indicates the level of sensitivity or criticality of the data. Multilevel Security (MLS) architecture is a system that supports data classification, which allows different levels of access to data based on the clearance and need-to-know of the users. Minimum query size is a parameter that can be used to enforce data classification, which limits the amount of data that can be retrieved or displayed at a time.

 When implementing a data classification program, it is important to avoid too much granularity, because the process will require too many resources. Data classification is the process of assigning a level of sensitivity or criticality to data based on its value, impact, and legal requirements. Data classification helps to determine the appropriate security controls and handling procedures for the data. However, data classification is not a simple or straightforward process, as it involves many factors, such as the nature, context, and scope of the data, the stakeholders, the regulations, and the standards. If the data classification program has too many levels or categories of data, it will increase the complexity, cost, and time of the process, and reduce the efficiency and effectiveness of the data protection. Therefore, data classification should be done with a balance between granularity and simplicity, and follow the principle of proportionality, which means that the level of protection should be proportional to the level of risk.

The other options are not the main reasons to avoid too much granularity in data classification, but rather the potential challenges or benefits of data classification. It will be difficult to apply to both hardware and software is a challenge of data classification, as it requires consistent and compatible methods and tools for labeling and protecting data across different types of media and devices. It will be difficult to assign ownership to the data is a challenge of data classification, as it requires clear and accountable roles and responsibilities for the creation, collection, processing, and disposal of data. The process will be perceived as having value is a benefit of data classification, as it demonstrates the commitment and awareness of the organization to protect its data assets and comply with its obligations.

Identity as a Service (IDaaS) is the best contract in offloading the task of account management from the IT staff. IDaaS is a cloud-based service that provides identity and access management (IAM) functions, such as user authentication, authorization, provisioning, deprovisioning, password management, single sign-on (SSO), and multifactor authentication (MFA). IDaaS can help the organization to streamline and automate the account management process, reduce the workload and costs of the IT staff, and improve the security and compliance of the user accounts. IDaaS can also support the contractors who have limited onsite time, as they can access the organization’s resources remotely and securely through the IDaaS provider.

The other options are not as effective as IDaaS in offloading the task of account management from the IT staff, as they do not provide IAM functions. Platform as a Service (PaaS) is a cloud-based service that provides a platform for developing, testing, and deploying applications, but it does not manage the user accounts for the applications. Desktop as a Service (DaaS) is a cloud-based service that provides virtual desktops for users to access applications and data, but it does not manage the user accounts for the virtual desktops. Software as a Service (SaaS) is a cloud-based service that provides software applications for users to use, but it does not manage the user accounts for the software applications.

The best description of the responsibilities of a data owner is determining the impact the information has on the mission of the organization. A data owner is a person or entity that has the authority and accountability for the creation, collection, processing, and disposal of a set of data. A data owner is also responsible for defining the purpose, value, and classification of the data, as well as the security requirements and controls for the data. A data owner should be able to determine the impact the information has on the mission of the organization, which means assessing the potential consequences of losing, compromising, or disclosing the data. The impact of the information on the mission of the organization is one of the main criteria for data classification, which helps to establish the appropriate level of protection and handling for the data.

The other options are not the best descriptions of the responsibilities of a data owner, but rather the responsibilities of other roles or functions related to data management. Ensuring quality and validation through periodic audits for ongoing data integrity is a responsibility of a data steward, who is a person or entity that oversees the quality, consistency, and usability of the data. Maintaining fundamental data availability, including data storage and archiving is a responsibility of a data custodian, who is a person or entity that implements and maintains the technical and physical security of the data. Ensuring accessibility to appropriate users, maintaining appropriate levels of data security is a responsibility of a data controller, who is a person or entity that determines the purposes and means of processing the data.

Technical and management teams will better understand the testing objectives, results of each test phase, and potential impact levels is the primary benefit of using a formalized security testing report format and structure. Security testing is a process that involves evaluating and verifying the security posture, vulnerabilities, and threats of a system or a network, using various methods and techniques, such as vulnerability assessment, penetration testing, code review, and compliance checks. Security testing can provide several benefits, such as:

• Improving the security and risk management of the system or network by identifying and addressing the security weaknesses and gaps
• Enhancing the security and decision making of the system or network by providing the evidence and information for the security analysis, evaluation, and reporting
• Increasing the security and improvement of the system or network by providing the feedback and input for the security response, remediation, and optimization

A security testing report is a document that summarizes and communicates the findings and recommendations of the security testing process to the relevant stakeholders, such as the technical and management teams. A security testing report can have various formats and structures, depending on the scope, purpose, and audience of the report. However, a formalized security testing report format and structure is one that follows a standard and consistent template, such as the one proposed by the National Institute of Standards and Technology (NIST) in the Special Publication 800-115, Technical Guide to Information Security Testing and Assessment. A formalized security testing report format and structure can have several components, such as:

• Executive summary: a brief overview of the security testing objectives, scope, methodology, results, and conclusions
• Introduction: a detailed description of the security testing background, purpose, scope, assumptions, limitations, and constraints
• Methodology: a detailed explanation of the security testing approach, techniques, tools, and procedures
• Results: a detailed presentation of the security testing findings, such as the vulnerabilities, threats, risks, and impact levels, organized by test phases or categories
• Recommendations: a detailed proposal of the security testing suggestions, such as the remediation, mitigation, or prevention strategies, prioritized by impact levels or risk ratings
• Conclusion: a brief summary of the security testing outcomes, implications, and future steps

Technical and management teams will better understand the testing objectives, results of each test phase, and potential impact levels is the primary benefit of using a formalized security testing report format and structure, because it can ensure that the security testing report is clear, comprehensive, and consistent, and that it provides the relevant and useful information for the technical and management teams to make informed and effective decisions and actions regarding the system or network security.

The other options are not the primary benefits of using a formalized security testing report format and structure, but rather secondary or specific benefits for different audiences or purposes. Executive audiences will understand the outcomes of testing and most appropriate next steps for corrective actions to be taken is a benefit of using a formalized security testing report format and structure, but it is not the primary benefit, because it is more relevant for the executive summary component of the report, which is a brief and high-level overview of the report, rather than the entire report. Technical teams will understand the testing objectives, testing strategies applied, and business risk associated with each vulnerability is a benefit of using a formalized security testing report format and structure, but it is not the primary benefit, because it is more relevant for the methodology and results components of the report, which are more technical and detailed parts of the report, rather than the entire report. Management teams will understand the testing objectives and reputational risk to the organization is a benefit of using a formalized security testing report format and structure, but it is not the primary benefit, because it is more relevant for the introduction and conclusion components of the report, which are more contextual and strategic parts of the report, rather than the entire report.

Remote access audit logs could cause a Denial of Service (DoS) against an authentication system. A DoS attack is a type of attack that aims to disrupt or degrade the availability or performance of a system or a network by overwhelming it with excessive or malicious traffic or requests. An authentication system is a system that verifies the identity and credentials of the users or entities that want to access the system or network resources or services. An authentication system can use various methods or factors to authenticate the users or entities, such as passwords, tokens, certificates, biometrics, or behavioral patterns.

Remote access audit logs are records that capture and store the information about the events and activities that occur when the users or entities access the system or network remotely, such as via the internet, VPN, or dial-up. Remote access audit logs can provide a reactive and detective layer of security by enabling the monitoring and analysis of the remote access behavior, and facilitating the investigation and response of the incidents.

Remote access audit logs could cause a DoS against an authentication system, because they could consume a large amount of disk space, memory, or bandwidth on the authentication system, especially if the remote access is frequent, intensive, or malicious. This could affect the performance or functionality of the authentication system, and prevent or delay the legitimate users or entities from accessing the system or network resources or services. For example, an attacker could launch a DoS attack against an authentication system by sending a large number of fake or invalid remote access requests, and generating a large amount of remote access audit logs that fill up the disk space or memory of the authentication system, and cause it to crash or slow down.

The other options are not the factors that could cause a DoS against an authentication system, but rather the factors that could improve or protect the authentication system. Encryption of audit logs is a technique that involves using a cryptographic algorithm and a key to transform the audit logs into an unreadable or unintelligible format, that can only be reversed or decrypted by authorized parties. Encryption of audit logs can enhance the security and confidentiality of the audit logs by preventing unauthorized access or disclosure of the sensitive information in the audit logs. However, encryption of audit logs could not cause a DoS against an authentication system, because it does not affect the availability or performance of the authentication system, but rather the integrity or privacy of the audit logs. No archiving of audit logs is a practice that involves not storing or transferring the audit logs to a separate or external storage device or location, such as a tape, disk, or cloud. No archiving of audit logs can reduce the security and availability of the audit logs by increasing the risk of loss or damage of the audit logs, and limiting the access or retrieval of the audit logs. However, no archiving of audit logs could not cause a DoS against an authentication system, because it does not affect the availability or performance of the authentication system, but rather the availability or preservation of the audit logs. Hashing of audit logs is a technique that involves using a hash function, such as MD5 or SHA, to generate a fixed-length and unique value, called a hash or a digest, that represents the audit logs. Hashing of audit logs can improve the security and integrity of the audit logs by verifying the authenticity or consistency of the audit logs, and detecting any modification or tampering of the audit logs. However, hashing of audit logs could not cause a DoS against an authentication system, because it does not affect the availability or performance of the authentication system, but rather the integrity or verification of the audit logs.

Operating System (OS) baselines are of greatest assistance to auditors when reviewing system configurations. OS baselines are standard or reference configurations that define the desired and secure state of an OS, including the settings, parameters, patches, and updates. OS baselines can provide several benefits, such as:

• Improving the security and compliance of the OS by applying the best practices and recommendations from the vendors, authorities, or frameworks
• Enhancing the performance and efficiency of the OS by optimizing the resources and functions
• Increasing the consistency and uniformity of the OS by reducing the variations and deviations
• Facilitating the monitoring and auditing of the OS by providing a baseline for comparison and measurement

OS baselines are of greatest assistance to auditors when reviewing system configurations, because they can enable the auditors to evaluate and verify the current and actual state of the OS against the desired and secure state of the OS. OS baselines can also help the auditors to identify and report any gaps, issues, or risks in the OS configurations, and to recommend or implement any corrective or preventive actions.

The other options are not of greatest assistance to auditors when reviewing system configurations, but rather of assistance for other purposes or aspects. Change management processes are processes that ensure that any changes to the system configurations are planned, approved, implemented, and documented in a controlled and consistent manner. Change management processes can improve the security and reliability of the system configurations by preventing or reducing the errors, conflicts, or disruptions that might occur due to the changes. However, change management processes are not of greatest assistance to auditors when reviewing system configurations, because they do not define the desired and secure state of the system configurations, but rather the procedures and controls for managing the changes. User administration procedures are procedures that define the roles, responsibilities, and activities for creating, modifying, deleting, and managing the user accounts and access rights. User administration procedures can enhance the security and accountability of the user accounts and access rights by enforcing the principles of least privilege, separation of duties, and need to know. However, user administration procedures are not of greatest assistance to auditors when reviewing system configurations, because they do not define the desired and secure state of the system configurations, but rather the rules and tasks for administering the users. System backup documentation is documentation that records the information and details about the system backup processes, such as the backup frequency, type, location, retention, and recovery. System backup documentation can increase the availability and resilience of the system by ensuring that the system data and configurations can be restored in case of a loss or damage. However, system backup documentation is not of greatest assistance to auditors when reviewing system configurations, because it does not define the desired and secure state of the system configurations, but rather the backup and recovery of the system configurations.

Security continuous monitoring is the program in which it is most important to include the collection of security process data. Security process data is the data that reflects the performance, effectiveness, and compliance of the security processes, such as the security policies, standards, procedures, and guidelines. Security process data can include metrics, indicators, logs, reports, and assessments. Security process data can provide several benefits, such as:

• Improving the security and risk management of the system by providing the visibility and awareness of the security posture, vulnerabilities, and threats
• Enhancing the security and decision making of the system by providing the evidence and information for the security analysis, evaluation, and reporting
• Increasing the security and improvement of the system by providing the feedback and input for the security response, remediation, and optimization

Security continuous monitoring is the program in which it is most important to include the collection of security process data, because it is the program that involves maintaining the ongoing awareness of the security status, events, and activities of the system. Security continuous monitoring can enable the system to detect and respond to any security issues or incidents in a timely and effective manner, and to adjust and improve the security controls and processes accordingly. Security continuous monitoring can also help the system to comply with the security requirements and standards from the internal or external authorities or frameworks.

The other options are not the programs in which it is most important to include the collection of security process data, but rather programs that have other objectives or scopes. Quarterly access reviews are programs that involve reviewing and verifying the user accounts and access rights on a quarterly basis. Quarterly access reviews can ensure that the user accounts and access rights are valid, authorized, and up to date, and that any inactive, expired, or unauthorized accounts or rights are removed or revoked. However, quarterly access reviews are not the programs in which it is most important to include the collection of security process data, because they are not focused on the security status, events, and activities of the system, but rather on the user accounts and access rights. Business continuity testing is a program that involves testing and validating the business continuity plan (BCP) and the disaster recovery plan (DRP) of the system. Business continuity testing can ensure that the system can continue or resume its critical functions and operations in case of a disruption or disaster, and that the system can meet the recovery objectives and requirements. However, business continuity testing is not the program in which it is most important to include the collection of security process data, because it is not focused on the security status, events, and activities of the system, but rather on the continuity and recovery of the system. Annual security training is a program that involves providing and updating the security knowledge and skills of the system users and staff on an annual basis. Annual security training can increase the security awareness and competence of the system users and staff, and reduce the human errors or risks that might compromise the system security. However, annual security training is not the program in which it is most important to include the collection of security process data, because it is not focused on the security status, events, and activities of the system, but rather on the security education and training of the system users and staff.

Guest OS audit logs are what an administrator must review to audit a user’s access to data files in a VM environment that has five guest OS and provides strong isolation. A VM environment is a system that allows multiple virtual machines (VMs) to run on a single physical machine, each with its own OS and applications. A VM environment can provide several benefits, such as:

• Improving the utilization and efficiency of the physical resources by sharing them among multiple VMs
• Enhancing the security and isolation of the VMs by preventing or limiting the interference or communication between them
• Increasing the flexibility and scalability of the VMs by allowing them to be created, modified, deleted, or migrated easily and quickly

A guest OS is the OS that runs on a VM, which is different from the host OS that runs on the physical machine. A guest OS can have its own security controls and mechanisms, such as access controls, encryption, authentication, and audit logs. Audit logs are records that capture and store the information about the events and activities that occur within a system or a network, such as the access and usage of the data files. Audit logs can provide a reactive and detective layer of security by enabling the monitoring and analysis of the system or network behavior, and facilitating the investigation and response of the incidents.

Guest OS audit logs are what an administrator must review to audit a user’s access to data files in a VM environment that has five guest OS and provides strong isolation, because they can provide the most accurate and relevant information about the user’s actions and interactions with the data files on the VM. Guest OS audit logs can also help the administrator to identify and report any unauthorized or suspicious access or disclosure of the data files, and to recommend or implement any corrective or preventive actions.

The other options are not what an administrator must review to audit a user’s access to data files in a VM environment that has five guest OS and provides strong isolation, but rather what an administrator might review for other purposes or aspects. Host VM monitor audit logs are records that capture and store the information about the events and activities that occur on the host VM monitor, which is the software or hardware component that manages and controls the VMs on the physical machine. Host VM monitor audit logs can provide information about the performance, status, and configuration of the VMs, but they cannot provide information about the user’s access to data files on the VMs. Guest OS access controls are rules and mechanisms that regulate and restrict the access and permissions of the users and processes to the resources and services on the guest OS. Guest OS access controls can provide a proactive and preventive layer of security by enforcing the principles of least privilege, separation of duties, and need to know. However, guest OS access controls are not what an administrator must review to audit a user’s access to data files, but rather what an administrator must configure and implement to protect the data files. Host VM access controls are rules and mechanisms that regulate and restrict the access and permissions of the users and processes to the VMs on the physical machine. Host VM access controls can provide a granular and dynamic layer of security by defining and assigning the roles and permissions according to the organizational structure and policies. However, host VM access controls are not what an administrator must review to audit a user’s access to data files, but rather what an administrator must configure and implement to protect the VMs.

According to the CXL blog2, the balance that must be considered when web application developers determine how informative application error messages should be constructed is risk versus benefit. Application error messages are the messages that are displayed or communicated to the users when an error or a problem occurs in the web application, such as a login failure, a form validation error, or a server error. Application error messages are important for the user experience and the conversion rate, as they help the users to understand and resolve the error or the problem, as well as to continue or complete their tasks or goals on the web application. However, application error messages also pose some risks or challenges for the web application developers, as they may reveal or expose some sensitive or confidential information about the web application, such as the system architecture, the database structure, or the security vulnerabilities, which may be exploited or attacked by the malicious users or hackers. Therefore, web application developers need to consider the balance between the risk and the benefit when determining how informative application error messages should be constructed. The risk is the potential or possibility of harm or damage to the web application, the data, or the users, as a result of the application error messages, such as the loss of privacy, integrity, or availability. The benefit is the value or advantage of the application error messages for the web application, the data, or the users, such as the improvement of usability, functionality, or security. Web application developers need to weigh the risk and the benefit of the application error messages, and decide how much and what kind of information to include or exclude in the application error messages, as well as how to present or format the information in the application error messages, in order to achieve the optimal balance between the risk and the benefit. Availability versus auditability is not the balance that must be considered when web application developers determine how informative application error messages should be constructed, as it is not related to the information or the presentation of the application error messages, but to the performance or the monitoring of the web application. Availability is the property that ensures that the web application, the data, or the users are accessible or usable when needed or desired, and are protected from unauthorized or unintended denial or disruption. Auditability is the property that ensures that the web application, the data, or the users are traceable or accountable for their actions or events, and are supported by the logging or recording mechanisms. Availability and auditability are both important for the web application, the data, and the users, but they are not the balance that must be considered when determining how informative application error messages should be constructed, as they do not affect or influence the information or the presentation of the application error messages. Confidentiality versus integrity is not the balance that must be considered when web application developers determine how informative application error messages should be constructed, as it is not related to the information or the presentation of the application error messages, but to the protection or the quality of the data. Confidentiality is the property that ensures that the data is only accessible or disclosed to the authorized parties, and is protected from unauthorized or unintended access or disclosure. Integrity is the property that ensures that the data is accurate, complete, and consistent, and is protected from unauthorized or unintended modification or corruption. Confidentiality and integrity are both important for the data, but they are not the balance that must be considered when determining how informative application error messages should be constructed, as they do not affect or influence the information or the presentation of the application error messages. Performance versus user satisfaction is not the balance that must be considered when web application developers determine how informative application error messages should be constructed, as it is not related to the information or the presentation of the application error messages, but to the efficiency or the effectiveness of the web application. Performance is the measure or indicator of how well the web application performs its functions or services, such as the speed, reliability, or scalability of the web application. User satisfaction is the measure or indicator of how satisfied the users are with the web application, its functions or services, or its user experience, such as the usability, functionality, or security of the web application. Performance and user satisfaction are both important for the web application, but they are not the balance that must be considered when determining how informative application error messages should be constructed, as they do not affect or influence the information or the presentation of the application error messages. References: 2

The type of encryption that is used to protect sensitive data in transit over a network is payload encryption and transport encryption. Encryption is the process of transforming or encoding the data or the information into an unreadable or unintelligible form, using a secret key or algorithm, to protect the data or the information from unauthorized access or disclosure. Payload encryption and transport encryption are the two types of encryption that are used to protect sensitive data in transit over a network, which means that the data or the information is being transmitted or communicated from one point to another point over a network, such as the internet, a local area network (LAN), or a wide area network (WAN).

• Payload encryption is the type of encryption that encrypts the content or the data of the message or the packet that is being transmitted or communicated over a network, such as the text, the image, or the audio. Payload encryption can protect the confidentiality or the secrecy of the data or the information, as it can prevent or reduce the risk of unauthorized or inappropriate access or disclosure of the data or the information by the third parties or the attackers who intercept or capture the message or the packet over the network.
• Transport encryption is the type of encryption that encrypts the header or the metadata of the message or the packet that is being transmitted or communicated over a network, such as the source, the destination, or the protocol. Transport encryption can protect the integrity or the accuracy of the data or the information, as it can prevent or reduce the risk of unauthorized or inappropriate modification or manipulation of the data or the information by the third parties or the attackers who intercept or capture the message or the packet over the network.
• B. Authentication Headers (AH) are not the type of encryption that is used to protect sensitive data in transit over a network, but rather the type of protocol or the mechanism that is used to provide the authentication or the verification of the source and the integrity of the data or the information that is being transmitted or communicated over a network, using a cryptographic checksum or a hash. AH can protect the authenticity or the legitimacy of the data or the information, as it can prevent or reduce the risk of spoofing, replay, or alteration of the data or the information by the third parties or the attackers who intercept or capture the data or the information over the network. However, AH does not provide the encryption or the protection of the confidentiality or the secrecy of the data or the information, as it does not encrypt the content or the data of the message or the packet over the network.
• C. Keyed-Hashing for Message Authentication (HMAC) is not the type of encryption that is used to protect sensitive data in transit over a network, but rather the type of algorithm or the technique that is used to generate the authentication or the verification code or the value for the data or the information that is being transmitted or communicated over a network, using a secret key and a hash function. HMAC can protect the authenticity or the legitimacy of the data or the information, as it can prevent or reduce the risk of spoofing, replay, or alteration of the data or the information by the third parties or the attackers who intercept or capture the data or the information over the network. However, HMAC does not provide the encryption or the protection of the confidentiality or the secrecy of the data or the information, as it does not encrypt the content or the data of the message or the packet over the network.
• D. Point-to-Point Encryption (P2PE) is not the type of encryption that is used to protect sensitive data in transit over a network, but rather the type of encryption that is used to protect sensitive data at rest on a device or a system, such as a point-of-sale (POS) terminal, a card reader, or a mobile device. P2PE is the type of encryption that encrypts the data or the information at the point of capture or entry on the device or the system, and decrypts the data or the information at the point of processing or storage on another device or system, using a secret key or algorithm. P2PE can protect the confidentiality or the secrecy of the data or the information, as it can prevent or reduce the risk of unauthorized or inappropriate access or disclosure of the data or the information by the third parties or the attackers who access or compromise the device or the system.

References: CISSP All-in-One Exam Guide, Eighth Edition, Chapter 4, page 115; Official (ISC)2 CISSP CBK Reference, Fifth Edition, Chapter 4, page 172