Online CC Questions Video

High availability (HA) refers to system designs that ensure continuous operation by minimizing downtime in the event of component failures. Adding a backup firewall that automatically takes over when the primary firewall fails is a classic example of high availability.

HA solutions often use failover mechanisms, heartbeat monitoring, and redundancy to ensure seamless service continuity. The goal is to maintain availability, which is a core pillar of the CIA triad.

Component redundancy describes duplicated parts, but high availability focuses on the operational outcome—continued service. Load balancing distributes traffic, not failover. Clustering involves multiple systems working together, but HA specifically emphasizes fault tolerance and uptime.

High availability is critical for security infrastructure such as firewalls, authentication servers, and monitoring tools. NIST and ISO frameworks stress HA as essential for business continuity, disaster recovery, and resilient security operations.

Security policies are high-level, mandatory statements approved by management that define security objectives, principles, and rules. Procedures and standards support policies but do not establish overarching intent.

Access control ensures that only authorized users can access specific resources. It includes authentication, authorization, and enforcement mechanisms.

Encryption protects data confidentiality, firewalls control network traffic, and antivirus detects malware. Only access control directly governs who can access sensitive information.

IPSec uses sequence numbers in AH and ESP headers to detect and reject duplicate packets. This prevents attackers from capturing and replaying valid packets. Anti-replay protection is a core IPSec security feature defined by the IETF.