Scenario 1

Let's say I have an internet router with a
firewall. Its Ethernet port has the IP address of and and a default route to
shoot everything out to the serial port. Then I
have a device (Device A) that's on a private IP
address, say And I have another
device (Device B) on Both these device
are on the same switch, and the router is also
connected to this switch. There's no DMZ

When A sends packets to B, what happens? Does the
packet go to the router, which the router will
receive through it's ethernet port, and then
route it back through the ethernet port? Will the
packet ever hit the firewall?

Scenario 2

Let's say Device B has an address of,
and the router has a NAT'd line for it that says
that is

Again, what happens when A sends packets to B?
Does it hit the router through the ethernet which
it'll just shoot right back out the ethernet


It's not a light at the end of the tunnel,
it's just another freight train headed your way.
A good friend will bail you out of jail, but your
best friend will be the one sitting next to you
saying "That was #%$&ing awesome!"