How Routering works?

[kevin@oceania.net]

I have been reading through The Networking Concepts HOWTO
and have a small query. My network looks like this

INET--ROUTER--FIREWALL--|= MASQERADED_NETWORK

>From what I can see a packet travesl from the 
intrnet to the router tho the firewall which
then masquerades/mangles the packet and it is
forwarded to the internal network.

How does the packet get from the router to the
firewall?

eg I have a server on 203.41.132.2
how does the router know to send the packet
to the firewall, is this because to the 
braodcast address?


Kevin