We are looking at options to expand our Domain to a couple of departments in our small city government. Currently these offices exist with isolated internet connections. We use Cisco ASA 5505 devices as our firewalls and were thinking of possibly using the Easy VPN feature to bring them into our network. I wanted to present the 3 solutions we have thought of so far and see if you Experts could provide other solutions for increasing our LAN.
Option 1: Metro Ethernet circuit rental through the local telephone provider 10 Mbps and $700/month not a good option given the cost
Option 2: VPN access to the Domain but we are in a rural area and internet speed is an issue. Each office currently only subscribes to DSL speeds of 256kbps but we could move up to 512 kbps or even 1024 kbps. Our hesitation is the VPN encryption may cause even the 512 speed to be too slow.
Option 3: Wireless connections via some wireless Bridge devices. This option will be incredibly expensive as we do not have line of site and will most likely require an omni-directional antenna on a tower. But it would be the fastest option at 54 mpbs. (radio speed)
I would like to get your help to create about 2 or 3 more options to network these satellite offices.