Azure VM to Microsoft Office 365 internet routing

Question

I have Azure Windows VMs that will require some users to connect to Office 365 for email and OneDrive uploads and downloads.

1. Is my business's Office 365 considered an Azure service?
2. Will the traffic leaving my VMs stay within Microsoft's network, or Azure backbone, instead of going out into the public Internet?
3. If it stays within Microsoft's network, does it incur the regular egress network charges leaving my VNet?

In Microsoft's Doc for virtual networks their statement reads:
Internet: Routes traffic specified by the address prefix to the Internet. ...If the destination address is for one of Azure's services, Azure routes the traffic directly to the service over Azure's backbone network, rather than routing the traffic to the Internet. Traffic between Azure services doesn't traverse the Internet, regardless of which Azure region the virtual network exists in

Answer 1

Hello @Cochise-Cloud ,

Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.

Any communication from azure VM for Office 365 for email and OneDrive uploads and downloads will be over public internet. It will not be through azure backbone network.

Office 365 for email and OneDrive are not azure services, here is the list of Azure Services https://azure.microsoft.com/en-in/services/.
If the destination address is for one of Azure's services, Azure routes the traffic directly to the service over Azure's backbone network, rather than routing the traffic to the Internet stands correct for those services listed in the above link.

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Answer 2

Reviewing a similar question for one of my customers, I found this answer and I thought it was correct at that time, however, looking a little bit deeper I found this article https://learn.microsoft.com/en-us/azure/networking/microsoft-global-network where states the below: "So, does that mean all traffic when using Microsoft services? Yes, any traffic between data centers, within Microsoft Azure or between Microsoft services such as Virtual Machines, Microsoft 365, XBox, SQL DBs, Storage, and virtual networks routes within our global network and never over the public Internet. This routing ensures optimal performance and integrity." so even Prrudram-MSFT statement is correct, it is not considered an Azure Service but belongs to the MS Global Network the traffic should be routed through the MS Backbone.