The Office of Electricity has partnered with Oak Ridge National Laboratory (ORNL) to lead an effort to establish the Center for Alternate Synchronization and Timing (CAST). Developed as part of the DOE funded DarkNet initiative that uses underutilized optical fiber to build a private, secure communication network, CAST was primarily created to decrease the vulnerabilities of Global Positioning System (GPS) signals by deploying a terrestrial based wide area signal system that provides alternative precision timing services for the nation’s power grid. In addition to providing new sources of robust timing data, the CAST system resists open-air or wireless jamming and spoofing attacks because it does not rely on weak, space-based GPS signals.

Utilities have traditionally been able to minimize their reliance on outside sources of information to reduce potential security issues, but they are finding it increasingly necessary to be able to receive data from external sources like GPS, network time protocol (NTP) timing, and some smart meters to manage their operations. While these new data streams from external sources have the potential to significantly enhance grid state situational awareness and facilitate new approaches for improving the reliability and resilience of the grid, they can also result in increased vulnerabilities.

DOE’s DarkNet initiative is a joint initiative by the Office of Electricity and the Office of Cybersecurity, Energy Security, and Emergency Response (CESER). Additional information on DarkNet and CAST can be found at