I have a customer for whom i have installed a few 2820vn routers, currently their isp provides firewalling through a cisco pix but this is about to change.

Is the firewall in the 2820vn good enough to protect a corporate network or do they/I need to go down a separate firewall route

cheers
Paul

The firewall rules work ok, but I would not use it for anything other than the small business/home office user.

You create filters which can be chained, but there is a limit on the number of rules per filter and a limited number of filters. For complex networks this can cause problems.

I would prefer more options or an ACL text filter for advanced users.

The Cisco PIX is generally a better firewall. My old netgear DG384 router firewall was easier to configure.