Azure Relay

Azure Relay

Azure Relay is a feature of the Microsoft Azure Service Bus service, offering two main capabilities: Hybrid Connections and WCF Relay.

Hybrid Connections allows for secure and reliable communication between two network applications using WebSockets or HTTP(S) for Request/Response, binary stream, or bi-directional communication. It does not require changes to security infrastructure in most cases, though exceptions may require opening firewall ports in restricted environments.

WCF Relay is the legacy relay capability used by customers with WCF programming models. It enables remote procedure calls (RPC) using the Windows Communication Foundation (WCF).

Azure Relay enables secure connections between corporate networks and Microsoft Azure. It supports communication types such as publish/subscribe scenarios for event distribution over the internet, bi-directional communication across network boundaries, and traditional one-way request/response communication.

History

On May 31, 2006, Microsoft announced the technology preview of Live Labs Relay, which allowed developers to create a local web service that could be accessed from anywhere. The preview was linked to a single machine, and anyone could sign up for testing.

Hybrid Connections

Hybrid Connection is a feature of Azure Relay, consisting of two components: the Azure Relay Service and the Azure App Service. It allows for bi-directional communication using HTTP and WebSocket protocols and can be used with any language on any platform. The communication is managed by a Hybrid Connection Manager (HCM) that uses the HTTPS protocol to communicate with Azure Relay. For improved security, Hybrid Connections supports TLS 1.2.

To learn more about Relay Hybrid Connections, see the following resources:

Relay Hybrid Connections HTTP in .NET

Relay Hybrid Connections HTTP requests in Node.js

Relay Hybrid Connections WebSockets in .NET

Relay Hybrid Connections WebSockets in Node.js

WCF Relay

WCF Relay is a legacy offering of the Azure Relay Service that utilizes the full .NET Framework over HTTP(S) and TCP (or "net.tcp") protocols. To use WCF, a connection is established between the on-premises service and the relay service through a suite of relay bindings. These bindings map to transport binding elements that create WCF channel components that integrate with the Service Bus Service.

The data transfer process involves the on-premises service connecting to Azure Relay through an outbound port. A bi-directional WebSocket is then generated to a specific address, allowing the client to communicate with the on-premises application by sending data to the relay address. The relay service then transfers the data to the on-premises via the dedicated bi-directional socket, without the need for direct connection to the on-premises service.

To get more information on WCF Relay, use some of the below links.

Expose On-prem WCF REST Service to Clients

Expose On-Prem WCF service to web Application

WCF Relay Security Feature: IP Firewalls

WCF Relay Security Feature: Private Endpoints

Additional Information

Videos

Azure App Service Hybrid Connections: Unsung Heroes of the Cloud, ep 17

Azure Friday | Azure App Service with Hybrid Connections to On-premises Resources

Training

Expose hybrid services securely with Azure Relay

Hybrid Connections VNET Integration

WCF Rest Tutorial

On-premises WCF service to a web application in the cloud

GitHub Projects

Hybrid Connections

WCF

References

This article "Azure Relay" is from Wikipedia. The list of its authors can be seen in its historical and/or the page Edithistory:Azure Relay. Articles copied from Draft Namespace on Wikipedia could be seen on the Draft Namespace of Wikipedia and not main one.

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