Case Study: Use of VWAN for Global Enterprise – Contoso Ltd.

Company Overview:

Contoso Ltd. is a global retail and manufacturing company with 20+ branch offices and manufacturing plants in North America, Europe, and Asia. Multiple Azure regions hosting apps, databases, and microservices. On-premises data centers in the US and Germany. High reliance on SaaS (e.g., Microsoft 365, Salesforce) and cloud-native applications.

They needed a robust and secure networking solution to ensure seamless connectivity between their global offices, on-premises data centers, and cloud resources.

Challenges:

1. Complex network topology using multiple VPNs, ExpressRoutes, and third-party SD-WAN.
2. High latency and inconsistent performance for remote branches.
3. Operational overhead for managing and troubleshooting site-to-site VPNs.
4. Security concerns in exposing branch traffic directly to the internet.
5. Lack of centralized visibility and policy enforcement.

Azure Virtual WAN (VWAN) vs. Traditional Hub-Spoke

Solution: Azure Virtual WAN

Azure Virtual WAN was deployed to simplify the network architecture and connect all branches, data centers, and Azure regions.

Architecture:

1. Hub-and-Spoke Topology:

• Virtual WAN Hub deployed in:
  • East US
  • West Europe
  • Southeast Asia
• Each hub includes:
  • VPN Gateway
  • ExpressRoute Gateway
  • Azure Firewall
  • Route tables
  • Custom policies

2. Connectivity:

• Branch Offices connect using SD-WAN appliances (e.g., Cisco, Palo Alto) or VPN devices.
• Data Centers connect via ExpressRoute into the hub.
• Spokes (VNETs) in Azure (e.g., App Services, databases) are peered to the hub.
• Remote Users use Azure VPN Client with P2S (Point-to-Site) VPN for secure access.

3. Routing:

• Azure Virtual WAN manages all routes via route tables and policies.
• Policies ensure all traffic from branches to the internet goes through Azure Firewall for inspection and logging.

Example Scenarios:

🔹 Scenario 1: Inter-branch communication

Employees in a Tokyo office need to access services in the Berlin manufacturing site.

• Both are connected to their local Azure hubs.
• Azure vWAN handles the routing through Microsoft’s backbone.
• Latency improves significantly (30–50% reduction).

🔹 Scenario 2: Cloud Application Access

Sales teams in remote offices access the company’s CRM hosted in Azure US-East.

• Instead of routing through corporate HQ, traffic goes through local hubs.
• Reduced backhaul, improved performance.

🔹 Scenario 3: Security Enforcement

All internet-bound traffic from branches is routed via Azure Firewall in the Virtual WAN hub.

• Threat protection, URL filtering, and logging implemented centrally.
• Meets regulatory compliance for traffic inspection.

Benefits:

Results:

• 50% reduction in VPN maintenance overhead.
• 30-40% better app performance across international branches.
• Unified policy management across hybrid and cloud networks.
• Faster onboarding of new offices (from weeks to hours).

Tech Stack Used:

• Azure Virtual WAN
• Azure Firewall
• ExpressRoute + VPN Gateway
• Azure Route Tables
• Microsoft Defender for Cloud
• Azure Monitor and Log Analytics

Summary:

Azure Virtual WAN is a networking service that simplifies and optimizes large-scale branch connectivity, hybrid networking, and remote user access by leveraging Microsoft’s global backbone and integrating multiple services into a unified, hub-and-spoke architecture.

References Courses:

AZ-700 Designing and Implementing Microsoft Azure Networking Solutions

AZ-305: Designing Microsoft Azure Infrastructure Solutions