Adding a 2nd Office

Hello,

My company is adding a 2nd office and I am not completely confident is what hardware I will need.

At our current office, we have a T1 for Voice, T1 for Data, a watchgaurd firewall, and with a gigabit switch layer 3.

At the new office we are getting a T1 as well. What else will I need as far as hardware goes in office 2 to connect both offices, share servers(files, etc), and share the VoIP(T1) from office 1.

Do I need to set up a permanent VPN? Not sure what way to go on this…any ideas? Thanks.