Hey guys. I've been researching the snot out of this and I'm looking for some advice.

I'm managing 3 offices over a slow link. It's a T-1 but, we're sharing so much bandwidth, we average between 50-100KBs inter-office speeds (we're inside a portal and share bandwidth with many other departments. And yes, I said 50-100 KBs over a T-1).

I'm looking to secure only LAN traffic over this link (Not internet bound traffic). What direction would you guys go? IPSec via Group Policy? Hardware Firewall with VPN? Software based VPN?

I don't need a full-blown solution, just a general direction to research. Thanks.