You want to block the "reserved purpose" ips in each range also, as in:
23.0.0.0-23.15.255.255
But the above entry, I can not find why I included it in my notes, it may have been a UK only something.
But, back on topic, For instance:
Code:
NetRange: 50.16.0.0 - 50.19.255.255
CIDR: 50.16.0.0/14
OriginAS:
NetName: AMAZON-EC2-8
NetHandle: NET-50-16-0-0-1
Parent: NET-50-0-0-0-0
NetType: Direct Assignment
The tool twobob used to convert CIDR must have been "protecting" the top and bottom two "special purpose" IP addresses of each range.
I am going to walk out onto the thinest of the ice and say those are the: "broadcast" and "anycast" addresses for each range.