Which method is commonly used to mitigate DDoS attacks?

Implementing rate limiting is an effective method for mitigating DDoS attacks because it controls the amount of traffic that a server will accept from a particular source or for a specific resource. By setting predefined limits on how often a user can request a resource, rate limiting can help to prevent overwhelming the server with excessive requests that are characteristic of DDoS attacks. This strategy allows legitimate traffic to flow while filtering out potentially malicious requests, effectively preserving the availability of the service.

Increasing bandwidth, while it may help accommodate a sudden influx of traffic, does not inherently address the unmanageable nature of DDoS attacks and may only serve as a temporary solution. Installing antivirus software primarily protects against malware and does not specifically target the distribution of excessive network traffic that a DDoS entails. Using multifactor authentication is focused on securing access to systems rather than managing and mitigating traffic volumes associated with DDoS threats.