I think this has been discussed many times. Basically, if you want to connect directly to database server over a VPN, you need a huge bandwidth (over 50-100MB i think).
Best way and most implemented architecture would be to have terminal services (either windows RDPs or Citrix) and allow all users to login remotely.
In my case, I use some 18 locations with 64KBPS IP/VPN bandwidth each to connect to a server on a 1MB leased line. Few more VPN links come through public internet from many parts of world using another DSL line. and all work without any issue. You may have increase site bandwidth based on the number of users at each location
HTH
"A bove maiore discit arare minor"-"From the old ox, the young one learns to plow."
Comments
Best way and most implemented architecture would be to have terminal services (either windows RDPs or Citrix) and allow all users to login remotely.
In my case, I use some 18 locations with 64KBPS IP/VPN bandwidth each to connect to a server on a 1MB leased line. Few more VPN links come through public internet from many parts of world using another DSL line. and all work without any issue. You may have increase site bandwidth based on the number of users at each location
HTH