AEM Dispatcher
Caching, security, and performance between AEM and the CDN
The AEM Dispatcher is the first line of defence and the primary caching layer between your AEM publish instances and the outside world. A well-configured Dispatcher dramatically reduces publish load, improves response times, and blocks malicious requests. A misconfigured Dispatcher leaks sensitive content, breaks author workflows, or silently fails to cache — causing unpredictable performance degradation under load.
Coverage
What this covers
Dispatcher Configuration for AEMaaCS
The AEMaaCS Dispatcher configuration model differs from AEM 6.x in important ways — immutable config, Docker-based local testing, and Flexible Mode rules.
Caching Rules & Strategies
Designing caching rules that maximise HIT rates without breaking personalised or session-aware content — including TTL strategies, selector handling, and extension whitelists.
Flush Agents & Cache Invalidation
Configuring flush agents to invalidate Dispatcher cache correctly after content publish — including selective invalidation strategies for large content trees.
Security Filters
Deny-by-default allow lists for URLs, headers, and parameters — blocking AEM admin interfaces, internal servlets, and common CMS attack vectors.
CDN Integration
How Dispatcher and CDN (Fastly, Akamai, CloudFront) work together in AEMaaCS — what each layer caches, how cache invalidation flows, and avoiding double-caching pitfalls.
Debugging Dispatcher Issues
Systematic debugging of cache misses, incorrect rewrite rules, and flush agent failures — using logs, curl, and the Dispatcher Docker image for local reproduction.
Differentiators
Why work with me
Both AEM 6.x and AEMaaCS experience
The Dispatcher configuration model changed significantly with AEMaaCS Flexible Mode. I have worked with both models and understand the migration path.
Security-first configuration
I treat Dispatcher security configuration as a non-negotiable baseline, not an afterthought. Every engagement starts with a review of what is and is not being blocked.
Performance measurement
Good Dispatcher configuration should be measurable. I help teams instrument cache HIT rates and TTFB so that configuration changes can be validated empirically.
Ready to discuss your AEM Dispatcher project?
Consulting, training, or advisory — reach out to find the right fit.
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