Currently, my company has three locations. The primary location is in the center of our state. We have one branch office aprox. 200 miles to the west and another branch office aprox. 200 miles to the south-east. Each office connects the main office via point to point T1 lines. All voice, data, and internet traffic is routed through our main office which houses all servers and our gateway which load-balances to ISP connections for the company web access.
I would like to propse that we transition to a VPN since the T1 connections will not be able to support all our traffic as we grow, transition to html based interface for our databases, and implement remote access for about 10-15 of our employees.
I beleive that a VPN is more redundant, scalable and modular than our current WAN. Are there reputable sources and/or standards to support this view?