This is a design question.
From what I have read, the UC320 does not have a built-in firewall.
If this is the case, it appears that I need a separate appliance to be my Internet firewall.
Is it standard practice to pass SIP through a separate firewall appliance, where this SIP trunk will terminate on my UC320?
My UC320 will be behind the firewall appliance: Internet -> Internet Firewall -> UC320--Lan--pcs and phones.