For business continuity, customer trust, and regulatory compliance, as the Chief Information Security Officer (CISO) of a publicly traded company, maintaining system availability is essential. In order to do this, I would put the following safeguards in place:

Redundant Infrastructure: Cloud environments and geographically dispersed data centers guarantee that operations continue even in the event of a system failure. Traffic is automatically rerouted by load balancing and failover techniques, which reduce downtime.

Web Application Firewalls (WAFs) and DDoS Protection: DDoS mitigation services, such as AWS Shield or Cloudflare, guard against excessive traffic that can impair system availability. WAFs provide extra security by sifting through online risks to provide uninterrupted access to systems for authorized users.

Plans for disaster recovery (DR) and backups:
To ensure that systems can be promptly restored in the event of system failures, ransomware attacks, or natural catastrophes, regular data backups and a tested disaster recovery plan with well-defined Recovery Time Objectives (RTOs) and Recovery Point Objectives (RPOs) are essential.

Patch management and vulnerability scanning: By locating and fixing vulnerabilities before they are exploited, proactive vulnerability scanning and routine patching assist avoid system compromise. This lowers the possibility of assaults or technical malfunctions causing downtime.

Monitoring and Incident Response: Early identification of performance problems or security concerns is made possible by continuous monitoring using SIEM solutions. Rapid recovery from disruptions is ensured by a well-prepared incident response plan, reducing the impact on availability.

Together, these safeguards ensure system availability and shield the business from monetary loss, harm to its reputation, and fines from authorities.