Azure Network and Caching for a Web Application

Azure provides load balancing, caching, and other network infrastructure for distributed applications. Several Azure infrastructure services that might be used for an Azure-hosted Web application are shown here in a hypothetical scenario.

A client sending a request first queries the name of the application through the organization’s Azure-hosted Domain Name System (DNS) server. The DNS server refers the client to an instance of Azure Traffic Manager. Traffic Manager selects a service endpoint based on an organization-configured policy. For example, it might select an endpoint in an Azure data center that appears to be closest to the client. The client connects to the IP address of the service endpoint to transmit the request.

The client connects to an Azure Application Gateway at the IP address and sends a request over a secure (HTTPS) connection. The Application Gateway decrypts the request, inspects it for possible risks (such as attempts to inject script via user input), and forwards the request to an Azure-hosted Web server drawn from a pool.