Rate limiting is a fundamental security control that restricts how many requests a user or IP can make in a given time period. It is essential for preventing abuse.
What is Rate Limiting?
Rate limiting controls the number of requests a client can make to your service within a specified time window. This prevents abuse from overwhelming your resources.
Effective rate limiting balances security (blocking attacks) with usability (not blocking legitimate users).
Rate Limiting Strategies
Fixed Window
Count requests in fixed time intervals (e.g., 100 requests per minute). Simple but can allow bursts at window boundaries.
Sliding Window
Smooth out request allowances over time, preventing boundary abuse.
Token Bucket
Allow bursts while maintaining a long-term average rate. Good for APIs with variable usage patterns.
Implementation Best Practices
- Layer Rate Limits - Apply different limits at network, application, and user levels
- Adjust by Reputation - Stricter limits for IPs with poor reputation scores
- Return Proper Headers - Include retry-after and remaining-requests headers for legitimate clients
Enhance Rate Limiting with Reputation
Use Fraudcache API to apply stricter limits to suspicious IPs.