ExpressRoute provides private network connectivity to Microsoft cloud services. Infrastructure and platform services running in Azure often benefit by addressing network architecture and performance considerations. Therefore, we recommend enterprises use ExpressRoute for Azure.
Software as a Service offerings, like Office 365 and Dynamics 365, were created to be accessed securely and reliably via the Internet. Therefore, we only recommend ExpressRoute for these applications in specific scenarios.
Important
Using ExpressRoute to access Azure is recommended for all enterprises. For guidance on using ExpressRoute to access Office 365 visit http://aka.ms/ExpressRouteOffice365.