static NAT on a 2651XM

[ingclientes]

Can anyone tell me how many static translations could a 2651XM support, considering about 10 Mbps traffic on an E3 interface (Frame Relay)

Thanks in advance

[tbaranski]

The limitation will probably be memory and there isn't any way to know for sure without testing. One of the Cisco folks here may know approximately how many bytes of memory a NAT entry uses, but this will be good for only rough estimations at best.

[a.manosca]

It's 160 bytes per translation.

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_q_and_a_item09186a00800e523b.shtml#Q6

[ingclientes]

Thanks.

Memory won't be an issue. What about CPU usage?

[a.manosca]

I believe that would depend on the level/type of translation you're going to use.

For example, High CPU utilization caused by IP Input:

"IP Network Address Translation (NAT) is configured on the router and there are lots of Domain Name System (DNS) packets going through the router. UDP or TCP packets with source and/or destination port 53 (DNS) are always punted to process level by NAT."

But with Cisco IOS 12.3, you can use the NAT Rate-Limiting feature:

http://www.cisco.com/en/US/products/sw/iosswrel/ps5207/products_feature_guide09186a00801d09f0.html