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Securing Voice Over Internet Protocol (IP) Networks



Thomas J. Walsh, David R. Kuhn


Voice over IP - the transmission of voice over traditional packet-switched IP networks - is one of the hottest trends in telecommunications. As with any new technology, VOIP introduces both opportunities and problems. Lower cost and greater flexibility are among the promises of VOIP for the enterprise, but security administrators will face significant challenges. Administrators may assume that since digitized voice travels in packets, they can simply plug VOIP components into their already-secured networks. Unfortunately, many of the tools used to safeguard today's computer networks, namely firewalls, Network Address Translation (NAT), and encryption, carry a hefty price when incorporated into a VOIP network. This paper introduces the security issues with VOIP and outlines steps that can be taken to operate a VOIP system securely.
ITL Bulletin -


telecommunications security, Voice over Internet Protocol, VoIP, wireless security


Walsh, T. and Kuhn, D. (2004), Securing Voice Over Internet Protocol (IP) Networks, ITL Bulletin, National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 17, 2024)
Created October 1, 2004, Updated February 19, 2017