A firewall is a hardware appliance that filters and blocks network traffic at the data layer. A WAF is an application firewall that inspects and filters HTTP/HTTPS communication to detect attacks at the application layer.
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What is a WAF?
A WAF is a software or appliance that filters, monitors, and analyzes hypertext transfer protocol (HTTP) and HTTPS traffic between a web application and the internet to identify, prevent and block common attacks. These include cross-site request forgery, server-side request forgery, file inclusion, and SQL injection. Attacks targeting these vulnerabilities are the leading cause of breaches, and a WAF protects against them by implementing both positive and negative security models.
Positive security models, like a club bouncer letting in those pre-approved, are implemented by defining the traffic the WAF allows. Negative security models are the opposite, defining what to deny and blocking everything else, and many WAFs offer both approaches to provide comprehensive protection.
WAFs can be software, appliances, or delivered as a service. They can also be network-based or host-based. A network-based WAF can be a hardware solution or a virtual security appliance on your servers. This can minimize latency and reduce security gaps. Host-based WAFs, on the other hand, can be fully integrated into an application’s software and are more customizable. However, they consume extensive local server resources and can be expensive to implement and maintain.
A cloud-based WAF can be a SaaS system, a VM-based software package, or a platform in front of your web servers. A cloud-based WAF can also offer a CDN, improving website load speed and protecting against distributed denial of service (DDoS) attacks.
What is a Firewall Manager?
A firewall manager is a central management service for web application firewall (WAF) rules, security policies, and configurations multiple accounts use. Firewall managers make it simple to collect and build rules, create policies, and deploy them to multiple accounts uniformly. This can help reduce the risk of a malicious attack, conflicting rules, or mistakes in firewall configuration. Firewall managers also provide a variety of other features to streamline the administration and maintenance of your network security infrastructure. These features can include standardizing rule naming conventions, ordering rules in a logical hierarchy, and providing automatic remediation for unused or outdated rules.
To use a firewall manager, you must join your account to an AWS Organization and designate it as the administrator account for the firewall manager. You must also create or have access to a security policy that will be used as the basis for the firewall manager.
Difference Between a WAF and a Firewall Manager
In WAF vs. firewall manager distinction, a WAF protects web applications from attacks by filtering traffic to and from the application. This enables businesses to detect attacks on OSI layer seven and other common attacks such as cross-site scripting, distributed denial of service (DDoS), and SQL injections. The WAF sits between the network and the web application, in a position known as inline, to analyze all HTTP communication to and from the web app.
Security administrators define rules that allow, block, or monitor web requests based on specific criteria, such as IP match, string matching, or vulnerabilities. Then they apply conditions to those rules to further narrow the allowed, blocked, or monitored requests. This enables security administrators to quickly record and block unauthorized or unwanted web traffic when incidents or compromises occur.
The best web application firewalls use machine learning to reduce the time-consuming manual effort required to configure, monitor and evaluate web security policies. This eliminates the need for security administrators to manually set up and maintain a rule base or perform other time-consuming activities, as well as protecting a broad range of advanced threats such as DDoS, protocol validation, bot mitigation, and more.
Difference Between a WAF and an NGFW
A WAF protects web applications on OSI model Layer 7 (web application protocols such as HTTP/HTTPS), thereby protecting against attacks such as cross-site scripting (XSS), SQL injection, and distributed denial of service (DDoS). A WAF can be hosted on-premise, in the cloud, or at a CDN.
Unlike a network firewall that focuses on network-layer attributes, a WAF examines and filters data packets at the application layer to detect attacks such as SQL injection and XSS that would be missed by traditional firewalls, which only look at IP addresses, ports, and protocol. WAFs can be configured to block certain kinds of attacks based on a list of rules (called a “blocklist” or a “blacklist”) or to allow certain traffic that meets specific criteria (called an “allowlist” or a “whitelist”).
A key challenge for most organizations is avoiding false positives, alerts sent to security teams by the firewall that mistakenly identify legitimate traffic as malicious. When false positives happen, correcting them can take time and resources and undermine an organization’s security posture. Fortunately, WAF is designed to minimize these issues by offering intelligent protection that eliminates many of the manual efforts required by other solutions, allowing security teams to focus on more high-impact threats. This is achieved through critical application fluency that automatically understands and learns normal traffic behavior over time and can differentiate between legitimate and malicious traffic.