FWIOS is much more powerful. Here are a list of things of the top of my head that FWIOS can do that PIX cannot.
* Policy based routing
* BGP (for advanced failover routing)
* ISDN and T1 termination
* QoS outside and inside an IPSEC tunnel (if you want to transmit things like VoIP and Video)
It's more expensive than a small PIX box, but there are no licensing restrictions on a router. On a 2600, just get the IOS with Firewall, IDS, and IPSEC feature set.
It really depends on your needs.
I'm seriously considering using the NetScreen 5GT or Fortinet boxes for the smaller offices because of their integrated Virus scanning capability on HTTP and FTP. They cost slightly more than a PIX 501 for less than $600. Sure I can build a dedicated transparent proxy server with gateway anti-virus, but the licensing alone will cost more than the 5GT. Sure it can handle a thousand users, but the massive throughput doesn't do me any good if I have fewer than 10 users in a small remote office. Cisco better wake up or else they'll find their market share shrinking soon, and I say this as a huge proponent of Cisco networking gear.
George Ou
Network Systems Architect
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