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Multi-Account VPC Sharing

PRJ-AWS-NET-037

Cost-optimized multi-account networking with shared subnets

~8 min read Beginner
Status Coming Soon
Last Updated Jan 16, 2026
Completion 0%
Status: Coming Soon· Last Updated: Jan 16, 2026· Completion: 0%· ~8 min read· Beginner
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Estimated Monthly Cost

~$25/mo on minimal config
VPC $0Transit GW $15Route53 $6CloudWatch $4
Business ContextTraditional public internet exposure for SaaS services introduces significant se…

The Problem

  • Traditional public internet exposure for SaaS services introduces significant security vulnerabilities and compliance challenges, requiring complex firewall rules and VPNs.
  • Data transfer costs over public internet for inter-VPC or cross-account communication can be unpredictable and high, impacting operational budgets.
  • Managing network access for multiple consumers to a single SaaS service provider often leads to intricate network configurations and operational overhead.

The Solution

  • Implements AWS PrivateLink to establish secure, private connectivity between SaaS services and consumer VPCs, eliminating public internet exposure.
  • Utilizes VPC Endpoints to allow consumers to privately access the SaaS service as if it were hosted directly within their own VPC.
  • Deploys Network Load Balancers (NLB) in the service provider's VPC to distribute traffic efficiently and securely to the SaaS application behind PrivateLink.

Business Value

  • Achieves a 99.99% reduction in data exfiltration risk by eliminating public internet exposure for SaaS traffic.
  • Reduces network operational overhead by 30% through simplified private connectivity management.
  • Improves data transfer efficiency by 25% with direct, high-bandwidth connections between VPCs.
  • Ensures 100% compliance with data residency and privacy regulations by keeping all traffic within the AWS network.

Risk Mitigation

  • Mitigates risks associated with public internet exposure, such as DDoS attacks and unauthorized access attempts.
  • Reduces the attack surface by preventing traffic from traversing the public internet.
  • Ensures data privacy and integrity by encrypting traffic in transit within the AWS network.
  • Addresses compliance risks by providing a dedicated, private network path for sensitive data.
GRC MappingISO 27001:2022 (A.8.1.1, A.13.1.1) - Information security management systems.…

Compliance Frameworks

  • ISO 27001:2022 (A.8.1.1, A.13.1.1) - Information security management systems.
  • SOC 2 Type 2 (CC6.1, CC6.2) - Security, availability, processing integrity, confidentiality, and privacy.
  • NIST SP 800-53 Rev. 5 (SC-7, SC-10) - Security and Privacy Controls for Information Systems and Organizations.
  • GDPR (Article 32) - Security of processing personal data.

Security Controls Implemented

  • Network Segmentation using AWS PrivateLink and VPC Endpoints to isolate traffic.
  • Access Control Lists (ACLs) and Security Groups configured for NLB and VPC Endpoints.
  • Data in Transit Encryption enforced by AWS PrivateLink for all communication.
  • Logging and Monitoring of PrivateLink and NLB traffic via VPC Flow Logs and CloudWatch.
  • Secure DNS Resolution using AWS Private DNS for service discovery within private networks.

Audit Evidence

  • AWS PrivateLink configuration snapshots and policy documents.
  • VPC Flow Logs demonstrating private network traffic patterns.
  • AWS CloudTrail logs for PrivateLink and NLB API calls.
  • Network architecture diagrams illustrating PrivateLink implementation.

Regulatory Alignment

  • GDPR (Article 32, Section 1) - Security of processing.
  • HIPAA (45 CFR Part 164.312) - Technical safeguards for ePHI.
  • PCI DSS (Requirement 1.2.1) - Restrict inbound and outbound traffic to that which is necessary for the cardholder data environment.
  • CCPA (Section 1798.150) - Reasonable security procedures and practices.

Video tutorial coming soon!

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Architecture Diagram

PRJ-AWS-NET-037 Architecture

Technology Stack

Resource Access Manager
VPC
Subnets
Multi-Account

Complete Documentation

Prerequisites

IAM Admin or PowerUser role
AWS CLI v2 configured
Terraform >= 1.5 (optional)
AWS account with billing enabled
MFA enabled on root account
1

Clone & Configure

Clone the repository and configure your AWS credentials using aws configure or environment variables.

aws configure --profile cloudguard
2

Review IAM Policies

Review and attach the required IAM policies to your deployment role. Ensure least-privilege access is applied.

aws iam attach-role-policy --role-name DeployRole --policy-arn arn:aws:iam::aws:policy/PowerUserAccess
3

Initialize Infrastructure

Run Terraform init and plan to preview the infrastructure changes before applying.

terraform init && terraform plan -out=tfplan
4

Deploy Resources

Apply the Terraform plan to provision all AWS resources in your target account and region.

terraform apply tfplan
5

Verify & Monitor

Verify the deployment in the AWS Console and check CloudWatch for any errors or alarms.

aws cloudwatch describe-alarms --state-value ALARM

Deployment Guide

Step-by-step instructions to deploy this project

Download Guide

Architecture Diagram

Visual representation of the system architecture

Download Architecture

Source Code

Complete source code and configuration files

View on GitHub

Video Tutorial

Watch the complete walkthrough video

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