One of our clients wants to be convinced that a powerful router (3700 & above)with FW IOS cannot replace a PIX FW in his network, which is comprised of a core router connecting to 6 routers via ATM and another router connected to the internet.
The main argument is whether to install FWs at the remote site (min 1000 employess each) or to have a FW IOS on the ATM routers, although he is not 100% sure of getting a FW behind his Internet router. I feel he is depending on the IOS FW way too much...
His arguments are as follows:
1- All ACL entries can be placed on the router instead of the FW, and performance is not that issue when installing powerful routers.
2- Redundant routers can be installed,hence the same result of PIX Failover.
He plans to buy IDSs for the sites which minimizes my headache, but I still want to know what important and convincing features he will be losing by replacing the pix FWs.
The Cisco IOS firewall can be a very solid choice for environments like you have described here. Multiple layers of security are of course always recommended, and an IDS/IPS solution would help to provide a very secure environment for your client. I would recommend a good read of the IOS firewall whitepaper at
which includes some info on redundancy and inspection limitations. One key point that you might note there is that the IOS Firewall doesn't support router redundancy, but does support interface redundancy and load sharing.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...