Options for connecting public api with on-premise API

Question

Hi,

I have question on connecting my Primary API to Secondary API in on-premise network.

Currently, Both the Primary and Secondary API are hosted in on-premise network.

I want to host the Primary API on Azure so that it can be publicly accessible to outside world. This Primary API needs to connect to on-premise API.

What are the options/approaches available through which I can connect my Primary API in Azure to my Secondary API in on-premise network.

Thanks

Answer 1

Hello Jeff green,

Welcome to the Microsoft Q&A and thank you for posting your questions here.

I understand that you're concerns to know options for connecting your public API with on-premises API.

To connect your Primary API hosted on Azure to your Secondary API in an on-premise network, you have several options.

1. Site-to-Site VPN, this allows secure communication between the Primary API in Azure and the Secondary API on-premises and alternatively, Point-to-Site VPN is an option if you have a smaller setup to connect individual devices to the Azure VNet - https://learn.microsoft.com/en-us/answers/questions/63939/creating-on-premise-api-using-azure-api-management
2. Azure ExpressRoute to create a private connection between your on-premises network and Azure. This provides higher bandwidth and lower latency compared to VPN - https://techcommunity.microsoft.com/blog/azurepaasblog/api-management---networking-faqs-demystifying-series-ii/1502056
3. You can use Azure API Management to manage your APIs such as Hybrid Connections or Self-hosted Gateway to connect on-premises APIs through VNet integration, allowing your Primary API in Azure to securely communicate with the Secondary API on-premises - https://learn.microsoft.com/en-us/answers/questions/1093610/api-management-with-public-on-premise-apis
4. Azure Relay is another option to securely expose your on-premises API to the cloud without opening a firewall connection. This allows your Primary API in Azure to communicate with the Secondary API on-premises - https://learn.microsoft.com/en-us/answers/questions/63939/creating-on-premise-api-using-azure-api-management
5. Azure Application Gateway with VNet integration is another option to route traffic from the Primary API in Azure to the Secondary API on-premise - https://learn.microsoft.com/en-us/answers/questions/63939/creating-on-premise-api-using-azure-api-management

I hope this is helpful! Do not hesitate to let me know if you have any other questions.

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