The majority of organizations rely heavily on third-party web applications connected through APIs to generate revenue and serve customers. In many cases, these web applications contain security vulnerabilities. And these vulnerabilities can potentially hurt your application and your business in general.

That’s why using a tool that offers you complete monitoring across your application and an in-depth protection solution is necessary.

In this post, we’ll see two of the most efficient security technologies: WAF and RASP. We’ll understand how they work and what their differences are, and finally, we’ll highlight the benefits of using them together.

What Is a WAF?

What Is a WAF?

A web application firewall, or better known as a WAF, acts as a monitor and a filter of a web applications’ HTTP traffic with the internet. WAFs serve as a defensive measure against several threats like cross-site scripting (XSS), impersonation attacks, XXE injections, misconfiguration attacks, malware attacks, and many others. WAFs prevent data leakage; therefore, they play a crucial role for businesses that provide their products online like banks, retail stores, and social media platforms, to name a few.

There are three different ways of WAF deployment: network based, host based, or cloud based. In general, WAFs are easy to deploy and maintain. They’re placed in front of web applications via a reverse proxy, serving as a protection layer between the applications and the internet. In contrast to a proxy server, a WAF protects from exposure by requiring clients to pass through the WAF before reaching the server. Due to their perimeter-based operation, WAFs don’t impact the application itself other than preventing incoming traffic.

WAFs have specific rules designed to protect application vulnerabilities by filtering out malicious traffic. These rules allow the quick and easy implementation of changes necessary to handle all the various attacks.

One of the advantages a WAF has over traditional firewalls is its advanced visibility into sensitive application data sent over the HTTP application layer. Also, it can prevent application-layer attacks that traditional firewalls are unable to stop. A WAF can protect an application without access to its source code.

Although WAFs are a great security measure, they cannot protect modern-day applications from all types of threats. Using them will help you prevent a series of risks, but you must combine them with other security tools to build a highly secure environment for your application.

Let’s talk a little more about that last point.

What Is RASP?

Often, applications are deployed in complex and often fragmented environments. This means that, in many cases, the application’s security architecture could be fragmented and complex as well. Things get worse, especially when there’s no thorough security plan. A traditional application security approach struggles to address complex security threats.

Runtime application self-protection, or RASP for short, primarily aims to address how developers respond to threats when they face them.

With RASP, application security gains a formal way to react to threats. It’s a powerful tool in your application security arsenal that allows you to identify vulnerabilities in the software’s application layer and address them in real time.

RASP is software that integrates with your application and tries to determine if something is attacking it by keeping track of calls made to the application and identifying them as threats or not. The difference between RASP and other protocols is that RASP instantly takes action and handles threats before they become a problem for the application. For example, RASP can terminate a call and prevent the user that initiated it from logging back in. Or it could ban the IP address that they’re using. RASP solutions eliminate vulnerabilities and protect from unknown zero-day attacks automatically and efficiently. They’re helpful even for legacy applications with a minimum level of application security. They offer a proactive solution in your production environment that will start giving you some protection against attacks.

Therefore, RASP offers a different security approach compared to more traditional ways. Since it blocks attacks in real time, RASP is an excellent fit for modern companies where the need for constant software upgrades is intense.

But although RASP has evolved application security, it’s not quite enough by itself.


Both WAF and RASP solutions specialize in delivering top-notch cybersecurity to web applications. While both solutions share the same goal, they do so very differently.


In general, web application firewalls protect against attacks across the entire infrastructure of an organization. They can detect and block threats from the beginning of the life cycle, but only through intensive web traffic monitoring. If the level of visibility isn’t sufficient, then a WAF might not offer full coverage. As a result, some threats may get through and harm the application.

WAF Use Cases

  • Protect web applications: WAFs can secure all web applications from common security threats, including OWASP’s top ten security risks.
  • Prevent DDoS attacks: A denial of service (DoS) is a security threat that makes a website, application, or system in general unavailable to end users. WAFs are a great solution against DDoS attacks. They control who can access the application and block malicious bots from repeatedly trying to access it.
  • Detect and analyze malfunctions: WAFs can be a central collection point for many types of log data. Although WAFs typically don’t analyze the log data themselves, they can send them to your SIEM tools to gain a larger context.
  • Filter content: A WAF can allow or block connections based on their content. Certain content types that are ambiguous, originated from non-accepted areas, or that, in general, don’t comply with your policies can be denied.

Although WAFs can be advantageous for these use cases, they do have their challenges, including the maintenance required from them being signature based.

WAF Use Cases

RASP Use Cases

Unlike WAF, RASP offers highly tailored security for each application. The RASP system monitors all aspects of the execution of an application. It can identify even unknown threats by analyzing the impact they have on the application they protect. Nevertheless, because RASP has to run locally on the device, general costs and the application’s performance might be affected.

  • Protect web applications: Using RASP, you can defend your application against known and unknown vulnerabilities ranging from CSS and RegDoS attacks to third-party connections and file sharing interfaces.
  • Implement API protection: API protection is more complicated than a typical application. RASP works at the application layer, making it an excellent solution for protecting such a vital part from malicious attacks.
  • Use a solution for modern workflows: RASP is excellent for agile and DevOps teams where on-time new feature delivery is essential. It acts as a safety net while development teams find and resolve potential security threats.
  • Have advanced visibility: RASP offers visibility that helps you know precisely which parts of your application are under attack so you can take all the necessary measures.
  • Protect cloud applications: Cloud application security is a complicated task because many different factors are involved and, in many cases, outside of the control of an organization. RASP’s cloud-agnostic characteristic offers applications a portable and high-security level.

Although RASPs can help with these use cases, due to their limited scope of visibility, there are inherent shortcomings with RASP solutions.

WAF and RASP Join Forces

RASP and WAF are two great but different tools for securing your applications. Combining them is a good solution to elevate your security, as they can mitigate each other’s limitations.

WAFs serve as the first security layer. They provide an overview of your application’s general activity, tracking odd patterns in large traffic volumes and blocking the bulk of web-based threats before they reach the application itself. Then, RASPs, which protect closer to the application, can find and eventually stop threats that will pass through the WAF layer.

Together, these tools can minimize the impact and protect against easy attacks and more complex and dangerous ones.



Securing your application against modern threats requires modern security solutions. Traceable AI combines the best aspects of WAF and RASP with AI and distributed tracing. It offers detailed insights into your entire application and detects and blocks malicious activity with high efficiency.

If you’d like to find out how a next-generation solution can secure your application, check out a demo of Traceable AI in action.