☁ AWS • CLOUD ARCHITECTURE • SECURITY

Enterprise AWS Secure Landing Zone

A secure and scalable multi-account AWS foundation designed around centralized governance, identity, networking, logging and cloud-security controls.

AWS Organizations Control Tower IAM SCP VPC CloudTrail Security Hub GuardDuty AWS Config
Independent & Sanitized Portfolio Case Study

This reference architecture is independently created to demonstrate AWS cloud architecture and security concepts. It contains no client architecture, employer information, proprietary code, account details or confidential data.

01 • THE PROBLEM

Scaling AWS Securely Across an Enterprise

As organizations increase their use of AWS, operating everything inside a small number of accounts can create challenges around security boundaries, access control, governance, networking, logging and cost ownership.

A well-designed landing zone establishes the cloud foundation before application teams begin deploying workloads at scale.

🏢 How should AWS accounts be organized?
🔑 How should workforce access be centrally managed?
🛡 How can organization-wide guardrails be enforced?
🌐 How should network connectivity be designed?
📜 Where should security logs be centralized?
🔍 How can security findings be centrally monitored?
02 • THE FOUNDATION

What is an AWS Landing Zone?

An AWS Landing Zone provides a structured foundation for operating multiple AWS accounts with consistent security, governance and operational controls.

Instead of allowing teams to create isolated cloud environments independently, the landing zone establishes common standards for account organization, identity, security, networking and logging.

🏢 Governance

AWS Organizations, organizational units and account structure.

🔑 Identity

Centralized workforce access and permission management.

🌐 Networking

Controlled connectivity between workloads and shared services.

🛡 Security

Centralized visibility, logging, detection and governance.

03 • ARCHITECTURE

Conceptual Multi-Account Architecture

The following architecture represents a fictional enterprise AWS environment designed with separation between platform, security and application workloads.

                       AWS ORGANIZATION
                              │
                     Management Account
                              │
          ┌───────────────────┼───────────────────┐
          │                   │                   │
          ▼                   ▼                   ▼
      Security OU        Infrastructure OU    Workloads OU
          │                   │                   │
     ┌────┴────┐          ┌───┴────┐         ┌────┴────┐
     │         │          │        │         │         │
 Log Archive  Security   Network  Shared     Prod      Non-Prod
  Account     Account    Account  Services  Accounts   Accounts
     │           │          │        │         │         │
     │           │          │        │         │         │
 CloudTrail   GuardDuty   Transit   DNS      VPCs      VPCs
 Config       Security    Gateway   Shared   Apps      Dev/Test
 Logs         Hub                   Services
     │           │
     └──────┬────┘
            ▼
   Central Security Visibility

       Organization-wide Guardrails
       ─────────────────────────────
          SCPs • Config • IAM
04 • ACCOUNT STRATEGY

Separation of Responsibilities

Management Account
AWS Organizations and organization-level administration.
Security Account
Centralized security administration and findings.
Log Archive Account
Protected centralized security and audit logs.
Network Account
Shared networking and connectivity services.
Production Accounts
Isolated business-critical production workloads.
Non-Production Accounts
Development and testing environments.
05 • GOVERNANCE

Organization-Wide Security Guardrails

Service Control Policies can establish permission boundaries across organizational units and AWS accounts while individual IAM policies continue to control permissions inside each account.

🏢 AWS Organization Central governance
📁 Organizational Units Group accounts by purpose
🛡 Service Control Policies Organization-level permission guardrails
🔑 IAM Permissions Account and workload access
Example Guardrails

Restrict unauthorized AWS Regions, prevent disabling security services, protect centralized logging resources and limit sensitive administrative operations.

06 • SECURITY OPERATIONS

Centralized Security Visibility

CloudTrail AWS Config GuardDuty Security Hub Investigation Remediation
Security Architecture Principle

Security telemetry should be centrally visible while sensitive audit data is stored separately from application workloads. This helps reduce the risk of workload administrators modifying or deleting critical security logs.

07 • SKILLS DEMONSTRATED

Cloud Architecture & Security Capabilities

AWS Multi-Account Architecture
AWS Organizations
AWS Control Tower
Service Control Policies
IAM & Identity Architecture
Network Architecture
Centralized Logging
Cloud Security Governance
AWS Security Hub
Amazon GuardDuty
AWS Config
CloudTrail
Next: Infrastructure as Code

This architecture can be extended with Terraform-based account provisioning, security controls, networking, centralized logging and automated cloud governance.