Microsoft a publié un article intéressant "Media Quality and Network Connectivity Performance in Skype for Business Online"
Description:
This topic defines the set of network performance requirements for Skype for Business Online services and how you can choose to use the Internet or ExpressRoute for connectivity between your network and Skype for Business Online based your assessment of the network connectivity. If you have decided to deploy Azure ExpressRoute for dedicated connectivity to Office 365, this document also provides guidance on how to plan your ExpressRoute connections in different Skype for Business Online deployment scenarios.