Task 5.3

I used for this task a different approach than the SG. I filtered the traffic with an extended ACL:

ip access-list extended DROP_TTL_LESS_13
 deny   ip any 224.0.0.0 15.255.255.255 ttl lt 13
 permit ip any any

and then applied it outbound on the interface:

interface FastEthernet0/0
 ip access-group DROP_TTL_LESS_13 out

Do you guys think this could be a valid solution?

Thanks.