Incapsula mitigated a rather small, 4Gbps DDoS attack, but this time it had a different pattern that attracted our attention. This time the attackers slipped-up and did not randomize the requests, making all the traffic arrive with the same IP TTL. The TTL parameter is part of the Internet Protocol. It’s a field that designates how many routers a packet is allowed to pass before it expires. It is almost impossible for a single machine to generate this kind of traffic.
Source: https://thehackernews.com/2013/04/who-needs-botnet-when-you-have-4-gbps.html