ExpressRoute lets you extend your on-premises networks into the Microsoft cloud over a dedicated private connection facilitated by a connectivity provider. With ExpressRoute, you can establish connections to Microsoft cloud services, such as Microsoft Azure, Office 365, and CRM Online. ExpressRoute connections do not go over the public Internet. This allows ExpressRoute connections to offer more reliability, faster speeds, lower latencies, and higher security than typical connections over the Internet.
Azure ExpressRoute for Office 365 ExpressRoute Pricing ExpressRoute Technical Overview Express Route Technical FAQ Office 365 network traffic management ExpressRoute prerequisites ExpressRoute QoS requirements ExpressRoute and QoS in Skype for Business Online ExpressRoute Service Level Agreement ExpressRoute Fridays (Channel9)