Cisco Router vs Cisco ASA vs SonicWall

[jonathanbaird]

Hi, 

I am a little confused as to what the difference is with a router and a firewall. Here is my issue... I understand a router, is for routing, but you can also use a router as a firewall, so what is the use of a firewall such as a Cisco ASA or a SonicWall? I also thought you could use a Cisco ASA or a SonicWall as a router, and a firewall, so what is the need for a router at all!? Do you need to use both and if you used both, what would happen with port forwarding. I'm really confused and any guidance would be fantastic!

Thank you.

[Richard Bradfield]

Jonathan,

Yes at a basic level routers and Firewalls are interchangeable. BUT once you get into the features of each you see the need for each

for example a router has buffers that allow for the difference in speed between a Gigabit interface and a Wan serial interface where as a Firewall would not,  also a Cisco ASA cannot do policy based routing whereas a router can For Firewalls the architecture is designed specifically for the purpose where as a Router the firewall function is an add on, so the Firewall performance is obviously better.

You just have to look at the Data sheets for each product to see the differences

HTH

Richard.