Azure Private Link Concepts

Azure Private Link provides the ability to access Azure Platform as a Service (PaaS) and Azure hosted customer-owned/partner services over a private endpoint in your virtual network. Traffic between your virtual network and the service travels the Microsoft backbone network, eliminating exposure from the public internet.

Private Link is a platform-as-a-service that provides a simple, intelligent, and secure networking capability. It enables you to ingest data from Azure services into your data warehousing solutions with Azure Data Factory. Private Link is also used to access Azure Storage or Azure SQL Database securely.

Key Concepts

1. Private Link Service

A Private Link service is an abstraction that you create on top of a network load balancer (NLB) in your service consumer's virtual network. It represents your service to be exposed privately.

The service is created in the consumer's virtual network.
It requires a standard SKU Internal Load Balancer (ILB) with at least one frontend IP configuration.
The ILB's backend pool is configured with the IP addresses of the service instances.

2. Private Endpoint

A private endpoint is a network interface that uses a private IP address from your virtual network, effectively bringing the Azure service into your virtual network. You can then group this private endpoint by a specific Azure service, such as Azure Storage or SQL Database.

A private endpoint is deployed into a specific subnet within your virtual network.
It receives a private IP address from the subnet's address range.
It provides secure, direct connectivity to the Azure service.

3. Connection

A connection represents the link between a private endpoint and a Private Link service. This connection is established after the service owner approves the connection request initiated by the service consumer.

Connections can be manually approved or automatically approved.
Once approved, traffic flows securely through the Microsoft backbone.

How it Works

When you create a private endpoint in your virtual network, it gets assigned a private IP address from that virtual network. Azure then creates a network interface (NIC) for this private IP. You can then use DNS to map the service's fully qualified domain name (FQDN) to the private IP address of the private endpoint.

This allows you to connect to Azure services as if they were in your own virtual network, without traversing the public internet. All traffic between your virtual network and the service is routed over the Microsoft Azure backbone network, providing enhanced security and reduced latency.

                
                    # Example of a Private Endpoint configuration (conceptual)
                    {
                        "name": "myPrivateEndpoint",
                        "location": "eastus",
                        "properties": {
                            "subnet": {
                                "id": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/myResourceGroup/providers/Microsoft.Network/virtualNetworks/myVnet/subnets/mySubnet"
                            },
                            "privateIPAllocationMethod": "Dynamic",
                            "privateLinkServiceConnections": [
                                {
                                    "name": "myConnection",
                                    "properties": {
                                        "privateLinkServiceID": "/subscriptions/00000000-0000-0000-0000-000000000000/resourceGroups/myServiceResourceGroup/providers/Microsoft.Network/privateLinkServices/myPrivateLinkService"
                                    }
                                }
                            ]
                        }
                    }
                
            

Benefits of Azure Private Link

Enhanced Security: Traffic stays within the Azure backbone, reducing attack surface.
Simplified Network Architecture: Eliminates the need for complex NAT gateway configurations or public IP management.
Consistent Connectivity: Provides a single way to access Azure services, whether they are PaaS, IaaS, or partner services.
Reliability: Leverages the robust Azure network infrastructure.