Old cisco router can be converted into NIce Firewall?

Hello, please helpme or giveme any idea for this:

I have this in my lan:

-Cablemodem Motorola whit working isp connection

-Router usr-8000A broadband whit NAT

-Two computers

-Old cisco 803(isdn)

well, i put cisco 803 on my lan in the DMZ of the router (no nat), all packets goto cisco 803 and i want to use this router as well Firewall.. its possible to filter all packets with Access list, etc?

Any idea?

I have a Cisco PIX 501 Firewall that I picked up on ebay to practice and work on my Cisco stuff. I wanted to configure it and also add it to my network as my firewall.

Has anybody worked with the Cisco PIX 501 Firewall and used it in there network.

ZiPPy

--I've not worked with Cisco PIX 501, but if you are looking for information on it, check this link.

www.cisco.com/en/US/products/hw/vpndevc/ps2030/ps2031/

Under Technical Documentation, you will see Configuration Examples. Hope it helps, if any.

I actually printed that info on the Cisco PIX501 Firewall about a week ago or so. I added it to my Cisco tech binder of info
Thanks for the link FallenZer0

ZiPPy