As the CISO for a publicly traded company it is a top priority to ensure all three principles of the CIA Triad, but there are certain protections I would implement to ensure the availability of my systems including redundancy and failover systems to distribute the demand over different servers with the help of load balancers to avoid server overload and downtime. I would also also implement traffic filters for filtering out fraudulent traffic and slowing down legitimate traffic to prevent them from overwhelming our network.