AWS Shield Protection Against Distributed Denial of Service (DDoS attacks) | Overview.

An Overview of AWS Shield.

• The Concept of AWS Shield,
• Table of AWS two tiers (Features & Pricing),
• How Shield Works (Layer by Layer),
• Layer 3/4 (Network & Transport Layers),
• Layer 7 (Application Layer)
• Architecture  & Data Flow (typical setup Shield in context),
• Data Flow Summary,AWS Shield Components, 
• Description & Integrations Table,
• AWS Shield Advanced for Detection & Mitigation,
• AWS Shield Advanced for Visibility,
• AWS Shield Advanced for DDoS Response Team (DRT),
• AWS Shield Advanced for Cost Protection,
• AWS Shield Advanced for Resource Coverage,
• Sample of AWS Shield + WAF + Global Accelerator Architecture,
• Benefits of this Architecture (AWS Shield + WAF + Global Accelerator),
• Steps in Detection & Mitigation Pipeline (Description & Tools)
• Best Practices,
• Visualization Diagram (AWS Shield Protection Layers),
• Comparison table for Shield Standard vs. Shield Advanced.

1. The Concept of AWS Shield

• AWS Shield is a managed protection service against Distributed Denial of Service (DDoS) 
• AWS Shield safeguards AWS applications against:
• volumetric, 
• protocol, 
• application layer attacks.

Table of AWS two tiers (Features & Pricing):

Tier	Key Features		Pricing
Shield Standard		Always-on protection against common network & transport layer DDoS attacks (e.g., SYN floods, UDP reflection, DNS query floods). Automatically included with all AWS resources.	Free
Shield Advanced		Enhanced, always-on detection and mitigation, visibility, cost protection, and 24x7 DDoS Response Team (DRT) support.	Paid (~$3,000/month per account + data transfer charges)

2. How Shield Works (Layer by Layer)

 Layer 3/4 (Network and Transport Layers)

•  Protects against:
•    Synchronize (SYN) /Acknowledgment (ACK) floods,
•    User Datagram Protocol (UDP) reflection attacks,
•    Internet Control Message Protocol (ICMP) floods
•    Connection exhaustion attacks.
• Shield automatically detects traffic anomalies by comparing live traffic against AWS baselines using flow sampling and anomaly detection algorithms.

 Layer 7 (Application Layer)

•  Shield integrates with AWS WAF to detect and mitigate attacks like:
•    Hyper Text Transfer Protocol (HTTP) floods
•    Slow POST/GET attacks
•    Excessive Application Programming Interface (API) calls
•  Attack patterns are analyzed using machine learning and rate-based rules.

3. Architecture & Data Flow (typical setup Shield in context):

Data Flow Summary:

    1. Traffic enters AWS Edge locations (CloudFront, Route 53, or Global Accelerator).
2. Shield detects & mitigates DDoS traffic (volumetric filtering, SYN proxying, etc.).
3. WAF applies rules (e.g., SQLi/XSS filters, rate limiting, IP blocks).
4. Clean traffic is forwarded to your application endpoints.

4. AWS Shield Components, Description & Integrations Table

Component	Description	Integration
Shield Standard	Always-on for all AWS services	Automatic
Shield Advanced	Enhanced protection with 24/7 DRT access	Manual enablement per resource
AWS WAF	Layer 7 filtering (custom rules)	Tight integration with Shield Advanced
AWS Firewall Manager	Central management for Shield + WAF	Enterprise use
Amazon CloudWatch	Real-time attack metrics, alarms	Integrated dashboards
Global Accelerator	Helps get a fixed IP + DDoS-resilient entry point	Works with Shield Advanced

5. AWS Shield Advanced

 A. AWS Shield Advanced for Detection & Mitigation

• Uses traffic baselines to detect anomalies.
• Employs automated mitigation systems for each AWS edge location.
• Mitigation time: usually sub-seconds to a few minutes.

 B. AWS Shield Advanced for Visibility

• Attack diagnostics in CloudWatch metrics and Shield Console:
•    Attack vector type
•    Volume (pps, bps)
•    Duration
•    Target resource
• Real-time notifications via Amazon SNS.

 C. AWS Shield Advanced for DDoS Response Team (DRT)

•  Available 24x7 for incident response and post-attack analysis.
•  Helps create tailored WAF rules or reroute traffic during attack.

D. AWS Shield Advanced for Cost Protection

•  Protects against scaling or bandwidth overage costs due to a DDoS.
•  AWS refunds the cost spikes caused by verified DDoS incidents.

 E. AWS Shield Advanced for Resource Coverage

twtech can attach Shield Advanced protection to:

•  Elastic Load Balancers (ALB/NLB)
•  Amazon CloudFront distributions
•  Global Accelerator accelerators
•  Route 53 hosted zones
•  EC2 instances (via Elastic IPs)

6. Sample of AWS Shield + WAF + Global Accelerator (Architecture Overview):

Data Flow:

    1.     Traffic hits Global Accelerator’s Anycast IPs (protected by Shield Advanced).
2.     Shield blocks volumetric DDoS traffic at the edge.
3.     WAF filters malicious Layer 7 patterns.
4.     ALB routes legitimate requests to backend.

Benefits of this Architecture (AWS Shield + WAF + Global Accelerator):

•  Fixed entry IPs (no exposure of ALB IPs).
•  Multi-layer protection (L3–L7).
•  Low latency via AWS edge routing.
•  Centralized logging and metrics.

7. Steps in Detection & Mitigation Pipeline (Description & Tools)

Step	Description	Tool
1	Traffic baselined & monitored	Shield sensors
2	Anomalous spikes trigger detection	CloudWatch alarms
3	Automated mitigation applied	AWS edge routers
4	Optional manual DRT involvement	Shield Advanced
5	Metrics & reports generated	CloudWatch + Shield Console

8. Best Practices

•     Use Shield Advanced for public-facing, business-critical applications.
•     Always pair Shield with AWS WAF for complete L3–L7 coverage.
•     Deploy Global Accelerator or CloudFront to terminate attacks at the edge.
•     Monitor Shield metrics in CloudWatch for baselines.
•     Configure automatic incident notifications (SNS + Lambda).
•     Enable AWS Firewall Manager for centralized policy enforcement.

9. Visualization Diagram (AWS Shield Protection Layers):

10. Comparison table for Shield Standard vs. Shield Advanced

Feature	Shield Standard	Shield Advanced
Network-level protection	✅	✅
Application-layer integration	🚫	✅ (with WAF)
DDoS cost protection	🚫	✅
CloudWatch metrics	Limited	Detailed
24/7 DRT access	🚫	✅
Attack diagnostics	Basic	Full
Resource coverage	Automatic	Manual per-resource