Azure Private Link Scenarios

Azure Private Link provides a secure and private way to access Azure platform-as-a-service (PaaS) services and Azure-hosted customer-owned/partner services from within your Azure Virtual Network (VNet). This document outlines common scenarios where Private Link is beneficial.

1. Secure Access to Azure PaaS Services

Many organizations need to access Azure PaaS services like Azure SQL Database, Azure Storage, Azure Key Vault, and Azure Cosmos DB. Traditionally, access might be through public endpoints, which requires network security configurations like firewalls and VNet service endpoints. Private Link offers a more secure alternative:

  • Eliminates Public Exposure: Traffic travels entirely over the Microsoft backbone network, never traversing the public internet.
  • Simplified Network Security: Reduces the complexity of managing firewall rules and network security groups for public endpoints.
  • Consistent Connectivity: Provides a consistent private IP address within your VNet for accessing the service.

Example: A web application hosted in an Azure VNet needs to securely store data in Azure Blob Storage. Using Private Link, a private endpoint is created in the VNet, allowing the application to connect to Blob Storage using a private IP address, bypassing public internet access.

Diagram showing VNet to Azure Storage with Private Link

Diagram: Private endpoint in VNet connecting to Azure Storage over Microsoft backbone.

2. Accessing Your Own Services Hosted in Azure

If you host your own applications or services within Azure, perhaps in a different VNet or subscription, Private Link allows you to expose these services securely to other VNets without exposing them to the public internet. This is particularly useful for SaaS offerings or internal shared services.

  • Private Service Exposure: Allows you to create a private endpoint for your service that consumers can connect to from their own VNets.
  • Multi-VNet/Multi-Subscription Access: Facilitates secure connectivity between services deployed across different VNets or subscriptions managed by different teams or customers.
  • Data Sovereignty and Compliance: Helps meet regulatory requirements that mandate data not to traverse public networks.

Example: A company offers a proprietary analytics service hosted on Azure Virtual Machines. They want to allow their enterprise customers to access this service privately from their respective Azure VNets. By using Private Link's "Private Link Service" feature, the company can provide a private endpoint for their analytics service.

3. Connecting to Partner Services

Many partners offer their services on Azure, and Private Link can be used to enable secure, private access to these partner services from your VNet.

  • Secure Partner Integrations: Enables seamless and secure integration with third-party solutions.
  • Reduced Attack Surface: By keeping traffic private, the risk of man-in-the-middle attacks or unauthorized access is significantly reduced.

Example: A financial institution needs to integrate with a partner's fraud detection service deployed on Azure. Using Private Link, the financial institution can connect to the partner's service privately from its own VNet.

4. Hybrid Connectivity with On-Premises Networks

While Private Link primarily focuses on connectivity within Azure, it can be part of a broader hybrid connectivity strategy.

  • Secure Ingress/Egress: When combined with Azure VPN Gateway or Azure ExpressRoute, traffic from on-premises networks can be routed privately to Azure PaaS services via Private Link.
  • Consistent Private Addressing: Allows on-premises resources to connect to Azure services using private IP addresses, simplifying routing and security configurations.

Example: An on-premises application needs to access Azure SQL Database. By establishing an ExpressRoute connection from the on-premises network to an Azure VNet, and then creating a private endpoint for Azure SQL Database within that VNet, the on-premises application can securely connect to the database.

5. Compliance and Data Security Requirements

For industries with strict compliance requirements (e.g., finance, healthcare, government), Private Link is invaluable for ensuring data stays within a private network boundary.

  • Meeting Regulatory Mandates: Helps organizations comply with regulations like GDPR, HIPAA, PCI DSS, etc., by preventing sensitive data from being exposed to the public internet.
  • Enhanced Security Posture: Provides a robust security layer by isolating traffic from the public domain.

By leveraging Azure Private Link, organizations can significantly enhance their security posture, simplify network management, and ensure compliance with data privacy regulations when interacting with Azure services and hosted applications.