Better Understanding of google motif/xmpp

Im wondering how does motif/xmpp connect to google?
If i have a firewall that block all incoming and outgoing connection but allow incoming and outgoing on the following IPs which is my internal network 192.168.0.x/24 will motif/xmpp still able to connect?
Do I have to allow a specific Google’s WAN IP to have it connect?
I have firewall that drop all connection except what is white listed.

Can anyone be of an assistance?
I got it to work fine, I want to know how it works?
Does xmpp/motif bind to my internal network then make a communication?

This is the wrong board for questions about this product.