integrate Azure cloud with datacenter on earth

azure1780 from the local data center the most key items is how is your identity flowing and where you want your authentication to happen in in the local data center or Azure or you want to do federation how you establish the connection Azure AD connect or SAML based identity providers etc. 

The other key element related to security how do you apply uniform security and also needs to consider who to minimize the risk when any one environment is compromised (On-prem compromised and what is the impact on Azure side and how to mitigate and vice versa.

Of course you have the whole sent of network segmentation and devices like firewall, VPN traffic encryption for S2S VPN or P2S VPN or express route that you have already called out 

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