When implementing Internet Protocol security (IPsec) architecture, the servers involved in application delivery communicate via Transport Layer Security (TLS), which is a protocol that provides encryption and authentication for data transmitted over a network. IPsec operates at the network layer and provides security for IP packets, while TLS operates at the transport layer and provides security for TCP connections. Blocking authorized users from unauthorized activities, channeling access only through the public-facing firewall, and channeling access through authentication are not functions of IPsec architecture. References: CISA Review Manual (Digital Version), Chapter 5, Section 5.4.2

Requirements analysis should be the best thing to compare against the business case when determining whether a project in the design phase will meet organizational objectives, because it defines the functional and non-functional specifications of the project deliverables that should satisfy the business needs and expectations. Requirements analysis can help evaluate whether the project design is aligned with the business case and whether it can achieve the desired outcomes and benefits. Implementation plan, project budget provisions, and project plan are also important aspects of a project in the design phase, but they are not as relevant as requirements analysis for comparing against the business case. References: CISA Review Manual (Digital Version), Chapter 4, Section 4.2.1

Internal firewalls are highly effective for isolating Internet of Things (IoT) devices from corporate network traffic. By segmenting the network and restricting communication between devices and the main corporate infrastructure, internal firewalls help mitigate the risk of lateral movement and data breaches caused by compromised IoT devices.
* Blockchain Technology (Option B):This is useful for ensuring data integrity but not for network isolation.
* Content Filtering Proxy (Option C):This is designed to manage web traffic and does not provide network segmentation.
* Zero Trust Architecture (Option D):While Zero Trust provides robust access controls, internal firewalls are more directly suited for traffic isolation.
Reference:ISACA CISA Review Manual, Job Practice Area 4: Protection of Information Assets.

Network segmentation is the best security measure to reduce the risk of propagation when a cyberattack occurs, because it divides the network into smaller subnetworks that are isolated from each other and have different access controls and security policies. This limits the spread of malicious traffic and prevents attackers from accessing sensitive data or systems in other segments. A perimeter firewall, a data loss prevention (DLP) system, and a web application firewall are also useful security measures, but they do not prevent propagation within the network as effectively as network segmentation does. References: CISA Review Manual (Digital Version)1, Chapter 5, Section 5.2.3