Let us look at another scenario. Assume that there is a distributed attack coming from the following IP addresses – 184.108.40.206 and 220.127.116.11. These two IP addresses have already been blacklisted by PortSIP PBX’s anti-hacking auto-detection mechanisms. You would, however, want to blacklist all the range, since you are sure that you will never get any traffic from these IP addresses. In this case, we will blacklist the whole range from 18.104.22.168 to 22.214.171.124, i.e. all the IP addresses that started with 41.202. 1.