WAF vs. Traditional Firewalls: Protecting Your Web Applications

If your business relies on web applications, you’re probably familiar with traditional network firewalls. And for good reason – they play an invaluable role filtering external threats looking to attack your overall infrastructure. But as more and more of your essential operations shift online to intricate web apps and APIs, gaps have opened up that basic firewalls simply can’t see into. 

Without visibility into your custom application logic and data flows, major vulnerabilities can be exploited, allowing sensitive information theft, financial fraud, and even operational disruption. So while you do need perimeter firewall defenses, exclusively relying on them to safeguard increasingly powerful web properties leaves you playing a risky game of chance. 

By adding specialized web application firewalls (WAFs) designed to analyze requests in the full context of your app environments, you can lock things down and confidently build out advanced digital capabilities. With a layered defense-in-depth approach combining network and application-level protections, you can securely deliver the types of seamless, personalized digital experiences that form the foundation of lasting customer relationships and operational excellence in 2024. 

Gaps In Traditional Firewall Defenses 

The chances are you already have traditional firewall protection guarding your overall network (if you run any online services). These firewalls filter incoming traffic based on a set of predefined rules focused primarily around protocol, port number, IP address ranges, and basic connection state. 

For example, common firewall rules restrict outside access to private intranet resources, block unwanted traffic types like online gaming protocols, detect large-scale network scans, and mitigate distributed denial of service (DDoS) attacks. 

This perimeter protection works well for classic network-focused cyberthreats. But a traditional firewall lacks context about the application logic, user workflows, and data structures unique to custom web apps and APIs. It simply scans network packets as they arrive and attempts to allow or block them accordingly. 

Without insight into application internals, major vulnerabilities can sneak right past traditional firewall defenses: 

• SQL Injection attacks inserting malicious code allowing remote access, data destruction, or information theft
   
• Broken authentication enabling unauthorized system access with stolen credentials
   
• Sensitive data exposure through improper encryption, backups, or logging
   
• Cross-site scripting (XSS) injecting JavaScript or HTML to spread malware, hijack sessions, scrape data, or deface sites 

Hackers can also target configuration issues, flawed business logic flows, identity management gaps, and unsafe object level access once inside applications themselves. 

And your firewall wouldn’t see it coming. 

These exploitable application flaws allow attackers to steal sensitive business data and personal information, mine cryptocurrency illicitly on servers, hold systems ransom, take over client accounts, and both deny legitimate access and destroy backend resources. 

Still, traditional firewalls remain extremely important as the first line of network perimeter defense. But for companies conducting operations online through modern web apps, additional safeguards tuned to application threats are essential. 

Why WAFs Provide Critical Protection 

Web application firewalls address the application layer vulnerabilities and holes in logic that basic network firewalls miss. WAFs are designed specifically to protect web apps, APIs, microservices, and rich internet applications. 

A WAF will deeply inspect all traffic flowing to web properties using targeted rulesets and negative security models defining suspicious behavior. From there, they analyze requests for indicators of common exploits and attacks seeking to abuse application behavior and functionality. These might include: 

• Extreme traffic spikes indicating possible DDoS events 
• Suspicious geolocations of an IP addresses 
• Repeated input submissions just below lockout thresholds 
• Unusual HTTP headers, user agents, or protocols 
• Known malicious payloads in POST requests 
• Attempts to traverse directory structures in unpredictable ways 
• Special characters and patterns indicating SQL injection or cross-site scripting 

Advanced WAFs combine this real-time threat detection with global threat intelligence to identify emerging exploits and bad actors as soon as new attack patterns appear. Machine learning algorithms even allow some solutions to derive additional behavioral rules by examining your specific application traffic patterns over time. 

As traffic passes through, the WAF blocks dangerous requests while allowing legitimate users through with minimal latency impact. This protects the application itself, shielding both data and functionality from compromise. 

Most WAF products also include capabilities like virtual patching, behavioral anomaly detection, automatic policy tuning, third-party integration, and positive security models for detecting verified use cases. 

Key Comparisons Between Traditional Firewalls and WAFs 

Feature	Traditional Firewall	Web Application Firewall (WAF)
Layer of Operation	Network (Layer 3/4)	Application (Layer 7)
Traffic Analysis	Packets, ports, IP addresses	HTTP/HTTPS requests, content, parameters, headers
Attack Protection	Network-level attacks	Web application-specific attacks (SQLi, XSS, CSRF, etc.)
Customization	Limited	Extensive
Additional Capabilities	May offer basic intrusion prevention	Often include bot mitigation, DDoS protection, API security

Creating An Application Security Ladder 

Web applications underpin many essential business capabilities – internal operations management, customer experience, partner integration – the list goes on. As reliance on these application ecosystems grows, so does business risk exposure through underlying vulnerabilities. 

Strengthening application security closes major blindspots while allowing companies to pursue advanced digital transformation supporting key goals around: 

• Improving self-service and convenience through customer portal expansion
   
• Accelerating development velocity using CI/CD pipelines and microservices
   
• Enabling real-time data exchanges through IoT integrations and open API ecosystems
   
• Increasing revenue with personalized interfaces and recommendation engines 

Combining network-layer perimeter defenses from traditional firewalls with reinforced protections from specialized WAFs creates a security ladder effect. The traditional firewall filters allowed traffic at the network level based on IPs, protocols, and volume heuristics. This protects against basic attacks like worms, reconnaissance scans, and DDoS events. 

Then the WAF takes over at the application layer, scrutinizing the full context of requests to identify attempts to exploit app logic and functionality itself using injection attacks, stolen credentials, unusual workflows, or other sneaky techniques security teams encounter daily. 

Together, this layered defense-in-depth approach secures both the overall network and the intricate web apps conducting an ever-larger percentage of essential business. Companies can then direct more development resources towards advancing capabilities rather than just patching vulnerabilities. 

Final Word 

The costs of security incidents grow more severe year over year. And as companies rely increasingly on web apps to manage operations, serve customers, and drive revenue, application vulnerabilities present a serious (and immediate) business risk. 

Protecting these systems with advanced application-aware defenses means that your security supports rather than hinders key strategic initiatives: 

• Improving self-service and convenience through customer portal expansion
   
• Accelerating development velocity using CI/CD pipelines and microservices
   
• Enabling real-time data exchanges through IoT integrations and open API ecosystems
   
• Increasing revenue with personalized interfaces and recommendation engines 

With scalable and secure defenses guarding your web properties, you can confidently build capabilities supporting goals around better customer experience, smoother operations, increased sales growth, and expanded partner channels. In other words, you can focus on pushing your business forward with the peace of mind knowing that you’ve done your part in securing your perimeter and web apps.