I have a general question regarding firewalls, but specifically as it pertains to the CBAC firewall feature set on, say, a 2811. Assuming that I have an ISR with a serial interface on the WAN side and an Ethernet as the LAN side, an ACL set up on the WAN side pointed inward (to filter incoming traffic.) Now, I have to decide which type of traffic the CBAC should inspect on the WAN interface (inbound or outbound). It makes sense to me that the inbound traffic should be inspected after it clears the acl (since we're trying to protect ourselves from internal threats.) Is there any reason to inspect traffic headed outbound from the LAN side?