The September 11, 2001, terrorist attacks on the World Trade Center and the Pentagon renewed concerns regarding physical threats to the public network (PN). While to date the telecommunications infrastructure has not been a direct target of terrorism, it could be in the future. Therefore, it is important that Federal, State, and local government assistance related to preventing, mitigating, and responding to such an occurrence be coordinated through the Telecommunications Information Sharing and Analysis Center (Telecom-ISAC). In addition to the enduring physical threat to the Nation's networks, cyber attacks present a growing threat to the security of U.S. information systems and consequently critical communications of the NS/EP community. As cyber network attack techniques increase in sophistication and intruders continue using DDoS techniques to exploit vulnerabilities, cyber attacks will likely cause greater collateral impacts to NS/EP communications. Because of this environment, industry and Government are focusing their efforts through participation in ISACs to further develop and implement unified and centralized capabilities to identify and mitigate the effects of an attack as it is occurring.