Pfsense sync between two nodes - how does it work?

[cwoehlk]

Hi, I'm new on this forum.
I recently started a school project where I have to configure pfSense, it works like a charm, but I'm curious to how the synchronization actually works (I hope this is the right place to put this up). 
So, my question is: how does the synchronization process work from the master to the backup. I have made a wireshark capture, but obviously it is encrypted, either i need it decrypted or if any of you brilliant minds knows how it works it would be great.
Does the master send an RPC request to the slave asking for the XML configuration or how does it work?
I'm doing my finals in January and i would like to learn more about this subject so that i can speak about it at my final exam.

Thanks in advance to anyone that might want to take the time and take a look at this.  :)
Also, please say if I need to specify something.  ;D