Shield Your Applications with AWS WAF Rate Limiting

 

AWS WAF (Web Application Firewall) offers robust protection for your web applications.

One critical feature is rate limiting, which helps mitigate DDoS attacks, brute-force attempts, and other abusive traffic patterns.  

Understanding Rate Limiting

Rate limiting restricts the number of requests that can be made within a specific time frame. This prevents malicious actors from overwhelming your application with excessive traffic.

Setting Up Basic Rate Limits with AWS WAF

1. Create a Web ACL: If you don't have one, create a new Web ACL in the AWS WAF console. 

2. Add a Rate-Based Rule: Under the "Rules" section, select "Add rules" and choose "Add my own rules and rule groups." Select "Rule builder" and choose "Rate-based rule" as the rule type.

3. Define Rate Limit Criteria: Specify the rate limit (number of requests), evaluation window (time period), and request aggregation (e.g., source IP).

4. Choose an Action: Select the desired action, typically "Block" to deny excessive requests.

5. Create the Rule: Complete the rule creation process and save the changes.

Additional Considerations

• Customizing Rate Limits: Adjust the rate limit and evaluation window based on your application's specific requirements.

• IP Whitelisting: Exclude trusted IP addresses from rate limiting to prevent false positives.

• Geo-Filtering: Limit requests based on geographic location to reduce attack surface.

• Monitoring and Analysis: Regularly review WAF logs to assess the effectiveness of rate limiting rules.

Best Practices

• Start with a Low Rate Limit: Begin with a conservative rate limit and gradually increase it as needed.

• Test Thoroughly: Implement rate limiting in a staging environment before deploying to production. 

• Combine with Other WAF Rules: Use rate limiting in conjunction with other WAF rules for comprehensive protection.

• Regular Review: Continuously monitor and adjust rate limits based on traffic patterns and threat intelligence.

By effectively implementing rate limiting with AWS WAF, you can significantly enhance your application's resilience against a variety of attacks.