Static NAT on Firewall and Dynamic NAT on Router

Posted on 2011-10-20
Last Modified: 2012-08-13
I am about to add a Cisco Router to our existing network where the SonicWall used to do everything before. The SonicWall Security Appliance currently does the firewall and static NAT for the servers. I was just wondering if there would be a performance, security or other issues if I added the dynamic NAT for the client computers on the Router so as to divide the processing for each device. In other words the firewall which already has static entries for the servers will remain as such and then I add a Cisco router that will assign the client computers with private IP addresses public IP addresses from a dynamic pool as needed. I just wanted to know if there would any issue with this kind of setup. Thanks.
Question by:Maximus54
    LVL 17

    Accepted Solution

    Depending on the model of Cisco router, moving the NAT to the router might severely cut into your performance ... especially with the smaller routers, once you move away from CEF, which you will for doing NAT, your spending lots of CPU cycles on this ...

    Author Closing Comment

    OK, thanks

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