firewall or router or both

a "so called" expert at work told me today that if I am running a router I do not need to run a firewall(currently using zonealarm), I have read about this and thought that I should run both, can someone who knows please answer this, I am asking b/c setting up my ps3 this weekend in wireless was a pita.

 

I run both without a problem. Recently I had the local tech guru help me install a wireless connection between my wife's computer, mine and our X-box 360. He agreed that both the router and software firewalls that we both have are great ideas for establishing a secure network. My wife uses ZA and I use Kerio.

 

A router is a good idea, no overhead in running it and is an element of defense in depth.

Software firewalls are also an element of defense in depth.

If you're on a LAN, a software firewall on the individual system would protect that system if the LAN got breached or went down or is mis configured, otherwise there is nothing there once past the router.

Another is outbound blocking, either to catch malware on the way out with whatever info, or to control the behavior of applications that want to connect.

Regards - Charles