APIs are the backbone of modern digital ecosystems, but their misuse can expose systems to cyber threats. Effective API throttling not only optimizes performance but also acts as a critical defense mechanism against abuse, such as denial-of-service attacks. Discover how this powerful strategy enhances API security and safeguards your organization’s data in an interconnected world.
What is API Throttling?
API throttling is a technique for controlling the rate at which clients can make requests to an API within a specified time frame. Its primary purpose is to prevent system overload, ensure fair resource distribution among users, and maintain consistent service performance and availability.
How Does API Throttling Work?
API throttling mechanisms are essentially an API’s bouncer. Just as a bouncer outside a club or bar turns away customers when the venue becomes too full, a throttling system turns away client requests when the server becomes overburdened.
Most API throttling systems will include one or more of the following concepts:
- Rate Limits: These act as guardrails, defining the upper boundary for the number of requests permitted within a specific timeframe.
- Burst Limits: Offer flexibility, allowing for temporary surges beyond the usual rate limit to accommodate urgent tasks or handle sudden traffic increases.
- Retry Mechanisms: Built-in safeguards that automatically reattempt failed requests after a brief pause, preventing service disruptions due to temporary rate limit exceedances.
Organizations implement API throttling by setting a limit on how many requests the API can receive in a specific time frame (system-level throttling) or how many requests a client can send in a specific time frame (user-level throttling). When the request limit is exceeded, the server issues a “429 Too Many Requests” code or other HTTP status code.
Why is API Throttling Important?
While we might primarily think of API throttling as an API security measure (an idea we’ll cover in more depth later), it has other equally important benefits. For example, it facilitates:
- Cost Savings: API throttling can reduce costs by minimizing the need for additional server capacity. Moreover, throttling systems reduce the risk of operational downtime, ensuring organizations can continue doing business, generate revenue, and avoid spending money on costly repairs.
- Resource Optimization: Without rate limiting, there’s nothing stopping clients from overusing or exploiting server resources. As such, throttling is especially important for organizations with high levels of online traffic, ensuring that all users get equal access to server resources.
- Improved User Experience: Similarly, API throttling helps ensure that an organization’s applications and services run smoothly, meaning clients and customers have seamless, streamlined, and equal user experiences.
- Future Proofing and Scalability: As enterprises expand, API requests increase. Implementing API throttling ensures that organizations can expand without their servers becoming overwhelmed by heightened demand.
Clearly, then, API throttling is an important measure for any organization that wants to remain competitive, operational, and innovative. However, its real value lies in its application for API security, as it can help prevent abuse.
Why is Throttling Important for API Security?
Throttling can have a massive impact on API security, protecting against threats to ensure the availability, stability, and security of an organization’s APIs. Let’s take a deeper look at how.
Mitigating Denial-of-Service (DoS) Attacks
Denial-of-service (DoS) attacks attempt to overwhelm an API with excessive requests, rendering it unavailable to legitimate users (denying the service). API throttling prevents attackers from flooding an API with requests and causing service disruptions by limiting the number of requests from a single source in a specified timeframe – ultimately mitigating the risk of a successful DoS attack.
Preventing Brute-Force Attacks
Brute force attacks involve testing as many passwords or API keys as possible to break into an API. Attackers may do this manually or, more commonly, with the aid of an automated tool. API throttling reduces the risk of a successful brute force attack by limiting the number of authentication requests, slowing down attackers, and granting administrators time to detect and respond to suspicious activity.
Ensuring Fair Usage
Some threat actors may monopolize an API’s resources to prevent other legitimate users from accessing them. Think of a shop where everyone wants to buy one in-demand item – without any rules, a few individuals could hoard all these goods and leave others empty-handed; this is analogous to an API without throttling. By setting usage limits, throttling prevents individual users or applications from monopolizing the API and impacting the experience of others – a concept known as fair usage.
Protecting Against Abuse
API abuse, such as excessive polling (repeatedly sending requests to a server’s API endpoint to check for updates or new data) and scraping (extracting data from a website by directly interacting with its API), can impact an API’s performance and availability. Again, throttling helps prevent API abuse by limiting the frequency of requests.
How Wallarm Can Help
Wallarm’s unified, best-in-class API Security and WAAP (Web App and API Protection) platform includes API Rate Limiting as standard, allowing our clients to effectively manage their service’s load and prevent false alarms, ensuring the service is always available and secure for real users.
What’s more, security teams can now set specific parameters and session settings to apply rate limit rules based on any request parameter, including JSON fields, base64 encoded data, cookies, XML fields, and more, and even adjust settings like the rate, burst, delay, and response code to fine-tune the rate limit settings and apply session settings to specific requests – all from the Wallarm Console. Want to find out more about what Wallarm can do for your organization’s API security? Request a demo today.