We are moving our setup to Azure. Due to the security requirements, we want to allow access to SharePoint Online(Part of Office 365) only to those users who are connected through Azure VPN. Any one trying to access SharePoint online, must not be allowed to do so.
Organization is of small number of users and all are mobile user who access the other azure infrastructure through Point to site VPN
We are also using Azure Active Directory services P1 and users are using Windows 10 laptop and we can consider them to domain join with Azure
This requirement is very critical