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New Member

PPPoa and Cisco ASA


I was wondering how the following situation can be handle. Is it possible to use a ASA if internet is established by a PPPoa (username/password required) ADSL modem? Let say a ASA is placed between a Exchange server (in a DMZ) and a PPPoA ADSL Router. Does the build-in NAT (ADSL Router) causes trouble? If an email must have access to the Exchange server then first the ADSL router must let it through (in most cases by configuring NAT port 25) before it can get to the ASA....sounds like a recipe for trouble..

* So, is it possible to use a ASA combined with a PPPoA (username/password required) internet line?

Everyone's tags (3)
New Member

Re: PPPoa and Cisco ASA

Well, no answers yet, but maybe I could resolve it myself....Cisco 800 series has ATM (PPPoA) support I guess, so maybe I should combine the Cisco 800 (in front) with the ASA 5500. It looks like no all-in-one solution is available (combination Cisco with ATM support and ASA) ...Ofcourse Routed Subnet makes life more easy...

Cisco Employee

Re: PPPoa and Cisco ASA


I would think that the best solution in this case is the following. Get a normal ADSL modem and configure it in bridge mode, so all the routing, nat and user authentication can be done on the ASA configuring PPPoE. Getting a ADSL Cisco router will be very expensive as it will only work as a "wire". I think this would be the easiest and cheapest solution.


Itzcoatl Espinosa