How does FortiGate handle DoS attacks?

FortiGate handles Denial of Service (DoS) attacks primarily through rate limiting and blocking traffic from sources that have been identified as malicious. This approach helps to mitigate the impact of such attacks by controlling the amount of requests that are directed toward a specific service, ensuring that legitimate users can still access the service even under the threat of an attack.

By limiting the rate of requests, FortiGate can effectively reduce the load on the target service that an attacker is trying to overwhelm, thereby maintaining service availability. Additionally, blocking malicious sources helps to prevent further attempts to disrupt services from known malicious entities. This strategy is essential in protecting network resources without entirely restricting legitimate traffic, which can happen if all incoming traffic were simply blocked or if only whitelisted IP addresses were allowed.

Increasing bandwidth or blocking all traffic could leave the network vulnerable or result in service denial for legitimate users, which is why rate limiting and targeted blocking are more effective and nuanced strategies in combating DoS attacks.