Voice over IP offers organizations lower telecommunications costs and greater network efficiency through convergence of voice, data and video. It can be used to stay connected during an emergency or calamity, giving employees access to their phone resources from IP phones at other locations. The rate at which VoIP is growing has given rise to network security concerns that need to be addressed as early as possible. NIST issued a report titled "Security Consideration for Voice Over IP Systems" last year, which focuses on VoIP security problems and recommendations, and highlights the current level of concern.