External Rate Limiting
Definition: External rate limiting is a technique used to control the rate at which external requests are processed by a system. It is typically implemented at the network or application level to prevent a system from being overwhelmed by a large number of requests.
How it Works:
External rate limiting works by setting a limit on the number of requests that can be processed per unit time. When a request is received, the system checks to see if the request rate is within the specified limit. If it is, the request is processed. If it is not, the request is either rejected or queued until the rate limit is no longer exceeded.
Benefits:
External rate limiting offers several benefits, including:
Examples:
External rate limiting is used in a variety of applications, including:
References:
Tools and Products for External Rate Limiting:
1. Nginx:
2. Apache Traffic Server:
3. Cloudflare:
4. AWS WAF:
5. Google Cloud Rate Limiting:
6. OpenResty:
7. Kong:
8. Tyk:
Related Terms to External Rate Limiting:
Throttling: Throttling is a general term used to describe the process of limiting the rate at which something is done. External rate limiting is a specific type of throttling that is applied to external requests.
QPS: QPS stands for queries per second. It is a common metric used to measure the rate of requests that a system can process. Rate limits are often expressed in terms of QPS.
RPS: RPS stands for requests per second. It is another common metric used to measure the rate of requests that a system can process. Rate limits are often expressed in terms of RPS.
Concurrency: Concurrency is the ability of a system to handle multiple requests at the same time. Rate limiting can be used to manage concurrency and prevent a system from being overwhelmed by too many requests.
Scalability: Scalability is the ability of a system to handle an increasing workload. Rate limiting can be used to help a system scale by preventing it from being overloaded.
Resiliency: Resiliency is the ability of a system to withstand and recover from failures. Rate limiting can be used to help a system be more resilient by preventing it from being overwhelmed by a large number of requests.
DDoS Attack: A DDoS attack is a type of cyberattack in which a large number of requests are sent to a system in order to overwhelm it and make it unavailable. Rate limiting can be used to mitigate the impact of DDoS attacks.
Prerequisites for External Rate Limiting:
Identify Critical Resources: Before implementing external rate limiting, it is important to identify the critical resources that need to be protected. This may include APIs, databases, or other services that are essential to the operation of your application.
Set Rate Limits: Once you have identified the critical resources, you need to set rate limits for each resource. Rate limits can be based on a variety of factors, such as the number of requests per second, the number of requests per user, or the size of the request payload.
Choose a Rate Limiting Mechanism: There are a variety of rate limiting mechanisms available, such as token buckets, leaky buckets, and sliding windows. You need to choose a rate limiting mechanism that is appropriate for your specific needs.
Implement Rate Limiting: Once you have chosen a rate limiting mechanism, you need to implement it in your application or infrastructure. This may involve configuring a web server, API gateway, or cloud service to enforce rate limits.
Monitor and Adjust Rate Limits: It is important to monitor the effectiveness of your rate limiting strategy and adjust rate limits as needed. You may need to increase rate limits during periods of high demand or decrease rate limits if you are experiencing performance issues.
Educate Users: It is important to educate users about your rate limiting strategy. This will help them understand why they may be experiencing delays and how to avoid exceeding rate limits.
Test Your Rate Limiting Strategy: Before deploying your rate limiting strategy to production, it is important to test it thoroughly. This will help you identify and fix any potential problems.
Next Steps After Implementing External Rate Limiting:
Monitor and Tune Rate Limits: Once you have implemented external rate limiting, it is important to monitor the effectiveness of your rate limits and adjust them as needed. You may need to increase rate limits during periods of high demand or decrease rate limits if you are experiencing performance issues.
Educate Users: It is important to educate users about your rate limiting strategy. This will help them understand why they may be experiencing delays and how to avoid exceeding rate limits. You can provide documentation, FAQs, or other resources to help users understand your rate limiting policy.
Consider Additional Security Measures: External rate limiting is just one part of a comprehensive security strategy. You should also consider implementing other security measures, such as authentication, authorization, and encryption, to protect your systems and data.
Plan for Scalability: If you expect your application or service to grow in popularity, you need to plan for scalability. This may involve using a cloud-based rate limiting service or implementing a distributed rate limiting solution.
Monitor for Abuse: Even with rate limiting in place, it is possible for attackers to abuse your system. You should monitor for suspicious activity and take action to block or mitigate abuse attempts.
Continuously Improve: External rate limiting is an ongoing process. You should continuously monitor, tune, and improve your rate limiting strategy to ensure that it is effective and efficient.
Consider Rate Limiting as Part of a Broader Security Strategy: Rate limiting is just one part of a broader security strategy. You should also consider implementing other security measures, such as authentication, authorization, and encryption, to protect your systems and data.