My ISP wants me to allow pings (ICMP) from their side to my router so they can notify me if my router or the circuit goes down. I guess it's been a long week and I can't think what I need my statement(s) to look like. On my router I have ACL 100 applied to outbound traffic on my serial interface and ACL 104 applied to inbound traffic. What statement(s) do I need to add to allow pings from my ISP's address 204.132.7.252/30?