Traffic by default, can travel "downward" (from a higher to lower security zone) freely without ACL's. If you are going from a private IP space to a public, you will need to NAT though (see above). Just NATAs long as there is no current ACL on the high security interface, an outbound NAT is all that is needed to allow outbound traffic flow. (you object network VIP_PAT
subnet 10.0.0.0 255.0.0.0
nat (inside,outside) dynamic 5.5.5.5
ACL and outbound NAT: | 