Origins of VoIP

 
Origins of VoIP
In November 1988, Republic Telcom (yes, one e) of Boulder, Colorado, received patent number
4,782,485 for a "Multiplexed Digital Packet Telephone System." The plaque from the Patent and
Trademark Office describes it as follows: "A method for communicating speech signals from a first
location to a second location over a digital communication medium comprising the steps of: providing a
speech signal of predetermined bandwidth in analog signal format at said first location; periodically
sampling said speech signal at a predetermined sampling rate to provide a succession of analog signal
samples; representing said analog signal samples in a digital format thereby providing a succession of
binary digital samples; dividing said succession of binary digital samples into groups of binary digital
samples arranged in a temporal sequence; transforming at least two of said groups of binary digital
samples into corresponding frames of digital compression."
Republic and its acquiring company, Netrix Corporation, applied this voice over data technology to the
data technologies of the time (X.25 and frame relay) until 1998 when Netrix and other competitors
introduced VoIP onto their existing voice over data gateways. Although attempts had been made at
Internet telephony from a software-only perspective, commercial applications were limited to using voice
over data gateways that could interface the PSTN with data networks. Voice over data applications were
popular in enterprise networks with offices spread across the globe (eliminating international interoffice
long-distance bills), offices where no PSTN existed (installations for mining and oil companies), and for
long-distance bypass (legitimate and illegitimate).
The popularity and applications of VoIP continued to grow. VoIP accounted for 6 percent of all
international long-distance traffic in 2001.[2] Six percent may not seem like an exciting sum, but given a
mere three years from the introduction of a technology to capturing 6 percent of a trillion-dollar, 100-yearold
industry, it is clear that VoIP will continue to capture more market share.