A very useful feature in Arbor DDoS is its ability to send flow spec announcements to routers. For example, if it is clear that a Layer 3 or Layer 4 attack is occurring and the attack pattern is identified through source and destination IP addresses and ports, you can generate flow spec filters. These filters are transferred through BGP to border routers, which automatically build filters, mitigating the attack even at the network's boundary and preventing it from reaching the TMS. This allows the TMS to focus on other tasks. This is a highly effective feature that can mitigate huge volumetric attacks; for example, we experienced a 32-gigabit attack, and all those 32 gigabits were dropped by our border routers, not by Arbor DDoS itself. The flow spec announcement was generated by Arbor DDoS, and as far as I know, the same technology is used by Radware, but it comes under a different feature and a different license. At the time, we were told that flow spec mitigation was an additional very expensive license to purchase from Radware, while Radware included everything in one package.
