[Asterisk-Users] Calling a registered computer

[jerk face]

I have two Asterisk servers: 
Box 1: Static IP address
Box 2: Dynamic IP address

I have Box 2 registered to Box 1 along with a switch
statement.
I can make calls from Box 2 to Box 1, but I am
wondering how can I make calls from Box 1 to Box 2?
Do I need to register Box 1 to Box 2, or is there a
simpler way?

I have searched the archives, but most messages deal
with the registration process, rather than what to do
after successful registration.

Thank you for your time.

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