Azure Routing Preference is now generally available
Published date: 09 March, 2021
Azure routing preference empowers you to choose how your traffic routes between Azure and clients on the Internet, letting you to optimise for performance or cost. You can choose between routing via “Microsoft Global Network” or routing via “Public Internet” that uses transit internet service provider (ISP) network. While the routing via Microsoft Network delivers traffic over an exceptionally reliable private global network optimised for performance, the ISP network option gives customers a cost optimised choice.
Egress data transfer price varies based on the routing selection. You can choose the routing option while creating a public IP address, and then associate with resources such as a virtual machine, an internet facing load balancer etc. You can also enable routing preference for storage services. By default, traffic is routed via the Microsoft global network for all Azure services.
You also get flexibility of enabling both routing options for the same resource. For example, you can have both routing choices enabled for your virtual machines with one public IP routed via Microsoft global network and another one routed via ISP network.
Routing via the Microsoft network: When you route your traffic via the Microsoft global network, traffic is delivered over one of the largest networks on the globe spanning over 165,000 fibre miles with over 180 edge Points of Presence (POPs). The network is well provisioned with multiple redundant fibre paths and traffic engineered intelligently to ensure exceptionally high reliability and performance.
Internet traffic enters and exits the Microsoft network closest to the user. By accepting and delivering the traffic to the point closest to the user, Azure provides optimised network experience (cold potato routing).
Routing via the transit ISP network: The new competitive egress tier minimises travel on the Microsoft global network and uses the transit ISP network. Internet traffic enters and exits the Microsoft network closest to the hosted service region (hot potato routing).