Due to the exhaustion of IPv4 (Internet Protocol version 4) address space, and the Office of Management and Budget (OMB) mandate that U.S. federal agencies begin to use the IPv6 (Internet Protocol version 6) protocol, NIST undertook the development of a guide to help educate federal agencies about the possible security risks during their initial IPv6 deployment. This document provides guidelines for organizations to aid in securely deploying IPv6. Since the majority of organizations will most likely run both IPv6 and IPv4 on their networks for the foreseeable future, this document speaks about the deployment of IPv6 rather than the transition to IPv6.