Telephony Denial of Service Fact Sheet

The public voice network has become the target of many attacks, including Telephony Denial of Service (TDoS), robocalls (automated telephone calls), SWATing (anonymously filing police reports to provoke a police raid) and bomb threats. TDoS is a flood of malicious inbound calls that target public-safety response systems such as 911. The Department of Homeland Security, Science and Technology Directorate (S&T) Distributed Denial of Service Defense (DDoSD) is working to shift the advantage from a DDoS attacker to the network administrator by developing the capability to authenticate callers and detect fraudulent call spoofing.