What is RateLimiting?
Rate limiting is a technique that controls how many times someone can ask a service to do something within a set period of time. It’s like a traffic cop that says “only X requests per minute” so the system isn’t overwhelmed.
Let's break it down
- Rate: the speed or frequency of something happening (e.g., how many requests).
- Limiting: putting a cap or maximum on that speed.
- Requests: the calls or messages a user or program sends to a server or API.
- Per time period: the limit is measured over a specific window, such as per second, minute, or hour.
- Service / API: the computer program or web service that receives the requests.
- Control: the act of managing or regulating the flow.
Why does it matter?
Because without limits, a single user or a bot could flood a system with too many requests, causing slowdowns, crashes, or extra costs. Rate limiting keeps services stable, fair, and affordable for everyone.
Where is it used?
- Public APIs (e.g., Twitter, Google Maps) that need to protect their data and infrastructure.
- Login pages that block repeated password attempts to stop brute-force attacks.
- Web scraping tools that must stay within a site’s allowed request rate.
- IoT platforms that manage thousands of devices sending data at once.
Good things about it
- Prevents server overload and downtime.
- Provides a fair share of resources for all users.
- Helps control operational costs by limiting excessive usage.
- Encourages developers to write more efficient, batch-oriented code.
- Improves overall reliability and user experience.
Not-so-good things
- May unintentionally block legitimate users, causing frustration.
- Adds extra configuration and maintenance complexity.
- Requires careful tuning; set the limit too low and you hinder usage, too high and you lose protection.
- Can introduce slight latency as requests wait for their turn.