The ASA 5580 is a pretty big firewall and it does not have a slot for an AIP-SSM IPS module. What model IPS sensor(s) do you have? Idealing you would like to monitor the DMZ and the internal network. Look at some traffic stats on your firewall to see if your sensor can handle the total bandwidth of both DMZ and Internal networks. Did you plan on putting your sensor in-line? Do you have enough sensor interface pairs?
