basic honeynet question

[mr () simla colostate edu]

im using the roo installation from www.honeynet.org and am having trouble understanding how the NIC cards are supposed 
to be set up.  they say 

* eth0 is the "Internet" or outside Interface
* eth1 is the LAN interface (Honeypot side)
* eth2 is the Management interface
* br0 is the virtual bridge interface (eth0 + eth1)

but i dont completly understand what that means.  is eth0 where the incoming connection comes, then eth1 is where the 
outbound packets are sent? also, do i need to set up a gateway before the honeypot? or can i user a router? im just 
really confused about how the physical networking is supposed to be done.  could someone give me some help?  thanks in 
advance