|Yes put in a dsl line but I would not connect it to the server.|
I would put in a firewall router that has vpn client support. Linksys has a couple of routers but the one I prefer is Sonicwall.
How this works is you setup a vpn client access list on the firewall.
You load the vpn software on the mobile client machine.
They connect to the internet, then run the client, put in their account name and password and are then connected to the network like they are on the local lan [they get a local lan ip address].
They then run RDP or other software to access the server.
Understand if you want to do RDP to the server you need to get TS/RDP licenses and setup RDP/Terminal services on the server. Otherwise any user using rdp is a ADMINISTRATOR on the server which is a really BAD idea.
If this seems too complicated consider setting up logmein, hamachi or gotomypc on a workstation at SiteA and use it to connect via the internet and to the server.
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