What is AWS WAF

Learn about AWS WAF, a managed firewall that protects your web applications from common web exploits.

What is AWS WAF
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AWS WAF (or Web Application Firewall) helps protect your web applications from common web exploits that could affect application availability, compromise security, or consume excessive resources. AWS WAF gives you control over which traffic to allow or block your web applications by defining customizable web security rules. You can use AWS WAF to create rules that allow or block web requests based on specific conditions, such as the IP addresses that requests originate from or the values of query strings. AWS WAF also lets you control access to your web applications using AWS Identity and Access Management (IAM) policies.

Why use WAF

AWS WAF gives you control over which traffic to allow or block your web applications. This can help protect your application from common web exploits that could affect availability, compromise security, or consume excessive resources.

AWS WAF can help improve the security of your website or web application in several ways:

  • AWS WAF gives you control over which traffic to allow or block your web application.
  • AWS WAF helps protect against common web exploits, such as SQL injection and cross-site scripting.
  • AWS WAF lets you control access to your content by IP addresses, countries, and other criteria.
  • AWS WAF integrates with other AWS services to give you additional layers of protection.
  • AWS WAF is easy to use, and there is no additional hardware or software to install.

How does WAF work

AWS WAF works by defining customizable web security rules. These rules can allow or block web requests based on conditions that you specify, such as the IP addresses that requests originate from or the values of query strings.

You can configure AWS WAF to suit your specific needs. For example, you can specify the following options:

  • The type of web traffic to allow or block (e.g., HTTP, HTTPS).
  • The specific URLs, IP addresses, or countries you want to allow or block.
  • The action to take when a rule is matched (e.g., block, authorize, or monitor).
  • The rate at which requests are allowed or blocked.
  • Whether to monitor all traffic or just traffic blocked by a rule.

AWS WAF also lets you create conditions, and groups of rules that you can apply to web requests. This can be helpful if you want to allow or block traffic based on multiple criteria. For example, you could create a condition that allows traffic from a specific country and blocks all other traffic.

Setting up WAF

To use AWS WAF, you first need to create a rule. Rules can be created using the AWS Management Console or the AWS WAF API. Once a rule has been completed, it can be applied to one or more web ACLs. Web ACLs are used to group rules together and can be associated with one or more web applications.

You can use AWS WAF to protect APIs hosted on Amazon API Gateway. To use AWS WAF with API Gateway, you first create an AWS WAF rule. Then, you add the rule to an API stage in API Gateway. API Gateway will then apply the rule to all requests made to the API. The cost of using AWS WAF with API Gateway is $5 per million API requests plus $0.02 per API Gateway hour.

You can use AWS WAF to protect applications running on Amazon Elastic Load Balancing (ELB). To use AWS WAF with ELB, you first create an AWS WAF rule. Then, you add the rule to a Load Balancer Policy in ELB. ELB will then apply the rule to all traffic routed through the load balancer. The cost of using AWS WAF with ELB is $2 per million web requests plus $0.02 per ELB hour.

WAF Best Practices

There are a few best practices to keep in mind when using AWS WAF:

  • Use AWS WAF to protect all of your web applications.
  • Create rules specific to your applications and the types of traffic you want to allow or block.
  • Use AWS Identity and Access Management (IAM) policies to control access to your AWS WAF resources.
  • Monitor the traffic to your web applications and the AWS WAF logs to identify potential attacks.

Pricing

AWS WAF is a pay-as-you-go service. You are only charged for the resources that you use. There is no minimum fee.

To see how AWS WAF pricing works, let's say you have a web application with an Amazon S3 bucket that stores sensitive data. You want to prevent all traffic from accessing the data in the bucket, except for traffic from a specific IP address range that you control. You also want to monitor all traffic to the bucket to see if anyone is trying to access the data.

First, you create an AWS WAF rule that allows traffic only from the specific IP address range. Then, you create an Amazon CloudFront distribution that uses the AWS WAF rule to restrict access to the bucket. Finally, you set up Amazon CloudWatch Logs to monitor all traffic to the bucket.

The total cost of using AWS WAF to protect your web application would be $0.60 per million web requests plus $0.02 per CloudFront distribution hour, plus the cost of Amazon CloudWatch Logs.

You can learn more about AWS WAF pricing here.

Conclusion

AWS WAF is a powerful tool that can help you protect your web applications from common exploits. By creating rules to allow or block traffic, you can control which traffic can access your applications. Additionally, using IAM policies can help you control access to your AWS WAF resources.