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Telephony Implications of Voice Over Internet Protocol

NCJ Number
Date Published
February 2006
2 pages
This paper discusses market trends and public safety concerns associated with the use of voice-over-Internet-protocol (VolP) communications.
VolP communications are all types of conversational voice information, including landline voice (telephony) or voice from a land mobile radio system. VolP technology allows voice communications to be transmitted digitally through a network that uses Internet protocol (IP) standards. VolP-based telephony is one of the fastest growing telecom technology sectors. Many businesses and commercial telephony service providers are changing to an IP-based infrastructure to take advantage of cost savings and the efficiencies of an IP transport network. In addition, nontraditional service providers have begun to compete with traditional providers by selling services that use the Internet, cable television network infrastructure, or other IP infrastructure to provide access to core transport network facilities. Two VolP categories can impact public safety: VolP telephony on public telephone networks and VolP technology within public safety radio systems. VolP-based telephony technology does not provide traditional location identification (enhanced 911 or E911) services for 911 emergency calls placed to a public safety answering point. A portable IP-based telephony device that operates through one or more public wireless WiFi access points will not even provide the limited details on location provided by a typical cellular telephone device. Another public safety concern is that traditional voice intercept and electronic surveillance techniques will become obsolete. IP addresses associated with a specific IP-based telephony device will change regularly, making it difficult or impossible to target a single device or user. Strong encryption between IP devices can further complicate the surveillance efforts of law enforcement agencies. 4 notes

Date Published: February 1, 2006