Web Application Firewalls: Tools and Solutions

Recommendation

Use the WAF on the traffic platform the team can observe and operate.

Compare Cloudflare, AWS, and Fastly by enforcement placement, rule model, false-positive workflow, application topology, logging, and incident ownership.¹ ²

For: Application, platform, and security teams operating internet-facing web applications and APIs

Main trade-off

A managed WAF can block known and custom HTTP patterns before application execution while adding rule tuning, false positives, visibility gaps, provider coupling, request-based cost, bypass risk, and incident-response work.¹ ² ³

Choose the control and ownership model

Start from the threat, protected asset, evidence obligation, or enforcement point before comparing products.

Traffic path
Map domains, APIs, CDNs, load balancers, origins, private ingress, direct-origin paths, websockets, protocols, and unsupported traffic.¹
Rule ownership
Define managed rules, custom rules, updates, scoring, exclusions, exceptions, virtual patches, staging, approvals, and emergency rollback.¹ ²
Signal and response
Require request visibility, matched-rule context, sampled payload controls, logs, alerts, investigation, false-positive review, and incident handoff.¹ ²
Economics and exit
Model requests, rule capacity, managed groups, add-ons, logs, support, domains, data, configuration export, and platform migration.³

Decision routes

Each route addresses a bounded security job and retains an explicit verification and failure boundary.

Cloudflare is authoritative for application edge traffic

Evaluate Cloudflare WAF.

Cloudflare WAF is the edge route when managed and custom rules should execute within an existing Cloudflare application-delivery boundary.

Verify: Verify DNS and proxy coverage, rulesets, overrides, exceptions, logging, false positives, origin bypass, plan entitlements, request pricing, and incident workflow.¹

HTTP applications are protected through supported AWS resources

Evaluate AWS WAF.

AWS WAF is the AWS-native route when web ACLs, managed or custom rules, logging, and supported AWS application resources form the operating boundary.

Verify: Model resource association, rule capacity, managed groups, exceptions, bot or fraud add-ons, logs, labels, false positives, requests, and AWS account ownership.²

Fastly's managed WAF deployment and operations model fits

Evaluate Fastly Next-Gen WAF.

Fastly Next-Gen WAF is the specialist managed route when its deployment options, rule and signal model, and Fastly operating workflow match the application.

Verify: Verify deployment placement, agents or edge coverage, rules, thresholds, exceptions, telemetry, false positives, support, pricing, and origin bypass.³

Boundary: A WAF applies HTTP request rules; Bot Protection evaluates automated actors, Rate Limiting enforces quota, and Vulnerability Scanning detects weaknesses that still require remediation.

Differences that change the control

Compare enforcement, evidence, operating ownership, failure behavior, sensitive-data exposure, and exit rather than marketing breadth.

Placement: Edge network, cloud resource, and specialist deployment models see different traffic and create different bypass paths.³

Rule lifecycle: Managed rules, custom logic, updates, capacity, exclusions, thresholds, and staging affect both coverage and false positives.¹ ²

Evidence: Match context, logs, payload handling, retention, alerts, and investigation access determine whether teams can operate the control.³

Mitigation boundary: A WAF can reduce exposure but cannot prove absence of vulnerabilities or replace secure design and remediation.¹ ²

Official resources

Verify current control boundaries, telemetry or evidence handling, deployment, limits, pricing, policy, and operating responsibilities in first-party material.

DocumentationCloudflare WAF documentation

DocumentationAWS WAF developer guide

DocumentationFastly Next-Gen WAF documentation

DocumentationNIST Secure Software Development Framework

PricingAWS WAF pricing