DJ
I agree with Jon that if you want to use the new address block for address translation for additional devices then all you need is a static route on your router pointing to the firewall (assuming that address translation is done on your firewall). Or if you want to use the new address block to assign addresses to additional devices then all you need on your router is a static route pointing to wherever the devices will be (presumably behind the firewall).
I would like to comment on something else in your post. You show a static default route pointing to the outbound interface:
ip route 0.0.0.0 0.0.0.0 FastEthernet0/0
While this may work it is very suboptimal. I would suggest these reasons why you want to do your static default route differently:
- this will work only if the next hop device supports proxy arp. If the next hop device does not support proxy arp then your static default route will not work. And increasingly organizations are disabling proxy arp because of security concerns.
- this static default route will cause your router to arp for every destination that it forwards to.
* arping for every destination will increase the CPU load on the router since the CPU is used to generate every request and to process every response.
* arping for every destination will increase the size of the arp table which will impact memory utilization on the router.
* arping for every destination will increase bandwidth utilization of the link from you to the provider. since it is Ethernet that may not be real significant.
* remember that arp entries are flushed and relearned every 4 hours. so the above points will occur for every address in the arp table every 4 hours.
HTH
Rick
HTH
Rick
