Best Practices for Leap Second Event Occurring on 30 June 2015

The DHS National Coordinating Center for Communications – COMM-ISAC has issued a paper titled "Best Practices for Leap Second Event Occurring on 30 June 2015." This paper is sponsored by the National Cybersecurity and Communications Integration Center (NCCIC) in coordination with the United States Naval Observatory, National Institute of Standards and Technology (NIST), the USCG Navigation Center, and the National Coordination Office for Space-Based Positioning, Navigation and Timing (PNT). The document can be found on the NAVCEN website at

The product is intended to assist federal, state, local, and private sector organizations with preparations for the 30-June 2015 Leap Second event. Entities using precision time should be mindful that no leap second adjustment has occurred on a non-holiday weekday in the past decade. Of the three leap seconds implemented since 2000, two have been scheduled on 31 December and the most recent was on Sunday, 1 July 2012.

Please report operational challenges you experience relating to the Leap Second insertion to the following organization:

GPS — United States Coast Guard Navigation Center (NAVCEN), via the NAVCEN Website, under "Report a GPS Problem"