Systems and methods for an information system security infrastructure are described. One embodiment of the present invention comprises global Internet-scale defense infrastructure, referred to as the Intrusion Detection Force (IDF). The IDF comprises a virtual infrastructure implemented on top of an existing network, such as the Internet. The IDF enables secure information sharing and intelligent data analysis and response. The node (e.g. 102 of FIG. 1) is the most primitive entity in the IDF architecture, and may be a switch, router, server, or workstation. The IDF may be implemented in small networks of computers or may be utilized by millions of hosts throughout the Internet, spanning different organizations, countries, and continents.