Exchange 2013 Architecture and migration

Hi all, I have two site 

Site A 
2 x Windows Server 2008 R2 Domains controllers 
4 x Exchange 2010 Servers 
Users are directly connected by LAN 

Site B 
2 x Windows Server 2008 DCs 

All services are in the same AD forest. 
The connection between the two Sites, Site A and Site B is using the Internet Site to Site VPN. 

It even attempt to install 2 Exchange 2013 servers in Site B and migrate mailboxes. 
Users access to email on the internet, while the VPN connection is for migrating mailboxes and Active Directory replication. 

THIS SETTING IS CORRECT? 

thank you very much

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Microsoft Certified IT Professional Server Administrator