Azure Front Door and Content Delivery Network (CDN)
5 minutes
5 Questions
Azure Front Door and Content Delivery Network (CDN) are two critical Azure services that enhance application delivery, performance, and security at the network edge.
**Azure Front Door** is a global, scalable entry point that uses Microsoft's global edge network to create fast, secure, and highly …Azure Front Door and Content Delivery Network (CDN) are two critical Azure services that enhance application delivery, performance, and security at the network edge.
**Azure Front Door** is a global, scalable entry point that uses Microsoft's global edge network to create fast, secure, and highly available web applications. It provides Layer 7 load balancing, SSL offloading, and application acceleration. Key security features include Web Application Firewall (WAF) integration, DDoS protection, and end-to-end TLS encryption. Front Door enables URL-based routing, session affinity, and health probes to ensure traffic flows to healthy backend endpoints. It supports multi-region deployments with automatic failover, making it ideal for mission-critical applications requiring high availability.
**Azure CDN** is a distributed network of servers that caches content closer to end users, reducing latency and improving load times. CDN stores static content like images, videos, JavaScript, and CSS files at edge locations worldwide. Azure offers multiple CDN providers including Microsoft, Verizon, and Akamai, each with unique capabilities. Security features include HTTPS support, custom domain SSL certificates, and token authentication for protected content delivery.
**Security Considerations:**
- Both services provide DDoS protection at the edge
- WAF policies can be applied to filter malicious traffic
- Private Link integration enables secure backend connections
- Custom rules can block specific geographic regions or IP addresses
- Bot protection identifies and mitigates automated threats
**Key Differences:**
Front Door excels at dynamic content acceleration and intelligent routing decisions, while CDN primarily optimizes static content delivery. Front Door offers more advanced security and routing capabilities, whereas CDN focuses on caching efficiency and global content distribution.
For comprehensive security architectures, organizations often combine both services to protect and accelerate their entire application stack, leveraging Front Door for dynamic APIs and CDN for static assets.
Azure Front Door and Content Delivery Network (CDN)
Why Azure Front Door and CDN Are Important
Azure Front Door and CDN are critical components for securing and optimizing web applications at the edge. For the AZ-500 exam, understanding these services is essential because they provide:
• DDoS Protection - Both services offer built-in protection against distributed denial-of-service attacks • Web Application Firewall (WAF) - Azure Front Door integrates with WAF to protect against common web exploits • SSL/TLS Termination - Secure traffic handling at the edge before reaching backend services • Global Load Balancing - Distributes traffic across multiple regions for resilience
What is Azure Front Door?
Azure Front Door is a global, scalable entry point that uses Microsoft's global edge network to create fast, secure, and highly available web applications. It operates at Layer 7 (HTTP/HTTPS) and provides:
• Global HTTP load balancing with instant failover • URL-based routing for microservices architectures • Session affinity for stateful applications • SSL offloading and certificate management • Custom domain support with automatic HTTPS
What is Azure CDN?
Azure Content Delivery Network (CDN) is a distributed network of servers that efficiently delivers web content to users. It caches content at strategically placed edge locations to minimize latency. Key features include:
• Static content caching for images, scripts, and stylesheets • Dynamic site acceleration for non-cacheable content • HTTPS support with custom domains • Geo-filtering to restrict content by country/region • Token authentication for protected content
How Azure Front Door Works
1. Traffic Reception - Client requests arrive at the nearest Front Door edge location 2. WAF Inspection - If enabled, WAF rules are applied to filter malicious traffic 3. Routing Decision - Front Door evaluates routing rules based on path, headers, or query strings 4. Backend Selection - Health probes determine available backends; traffic is routed based on latency or priority 5. Response Delivery - Content is returned through the edge, with optional caching
Security Features of Azure Front Door
• Web Application Firewall (WAF) - Protects against SQL injection, XSS, and OWASP top 10 vulnerabilities • Bot Protection - Identifies and blocks malicious bots • Rate Limiting - Controls request rates to prevent abuse • Private Link - Secure connectivity to backend origins • Managed Certificates - Automatic SSL certificate provisioning and renewal
Azure Front Door Tiers
• Azure Front Door Standard - Content delivery optimized with basic security • Azure Front Door Premium - Includes advanced WAF, bot protection, and Private Link support
Exam Tips: Answering Questions on Azure Front Door and CDN
1. Know the Differences Front Door is for global load balancing and application acceleration with advanced routing. CDN is primarily for caching static content. Questions may test whether you can select the appropriate service.
2. WAF Integration Remember that WAF policies can be associated with Front Door to protect web applications. Know the difference between detection mode and prevention mode.
3. Routing Methods Understand Front Door routing methods: • Latency-based - Routes to the lowest latency backend • Priority-based - Routes to primary backend, fails over to secondary • Weighted - Distributes traffic based on assigned weights
4. Health Probes Front Door uses health probes to determine backend availability. Know that you can configure probe intervals, paths, and protocols.
5. SSL/TLS Settings Expect questions about minimum TLS versions and cipher suites. Front Door supports TLS 1.2 as minimum by default for security compliance.
6. Private Link for Premium Tier Azure Front Door Premium supports Private Link to securely connect to backend services through private endpoints. This is a key security feature for exam questions.
7. Geo-Filtering vs. Geo-Routing CDN geo-filtering blocks or allows content by region. Front Door geo-routing directs traffic to specific backends based on user location.
8. Caching Behavior Understand cache configuration options including cache duration, query string caching, and cache purging mechanisms.
9. Custom Domains and HTTPS Know how to configure custom domains with Front Door and the options for managed certificates versus bring-your-own certificates.
10. Common Exam Scenarios • Protecting a multi-region web application from DDoS and web attacks → Azure Front Door Premium with WAF • Accelerating static website content globally → Azure CDN • Securing backend APIs with private connectivity → Front Door Premium with Private Link • Implementing URL-based routing for microservices → Azure Front Door with routing rules