Thanks for your response. We have a DSL connection that is a backup to our Fractional T1. This interface is intended to only handle the DSL backup and will either be unplugged or the interface will be set to DOWN unless we lose our T1. I mainly just want to make sure the Routes and groups are still applied to this interface. It will have a seperate IP of course. My first question was to make sure that I COULD add this interface with my current license.

Roger,

If I recall correctly if you have an (R) lisence in your PIX 515E it will support up to 3 interfaces, if you have a (UR) license it will support maximun interfaces which is a total of 6 physical interfaces. The way to tell your license is by issuing show version and take note the R or UR in output.

So if you install another single 10/100 NIC card and your PIX have R license you should be fine, I would recommend installing a quad card to give you 4 physical interfaces so that you don't waste a single NIC if needing to upgrade to quad card later , you should be able to buy a quad card cheap these days between $100-200, it will save you headaches down the road.

http://www.cisco.com/en/US/prod/collateral/vpndevc/ps5708/ps5709/ps2030/product_data_sheet09186a00800b0d85.html

HTH

Jorge