Voice Over IP - Historical Milestones

Historical Milestones

• 1973: Network Voice Protocol (NVP) developed by Danny Cohen and others to carry real time voice over Arpanet
• 1974: The Institute of Electrical and Electronic Engineers (IEEE) published a paper titled "A Protocol for Packet Network Interconnection".
• 1974: Network Voice Protocol (NVP) first tested over Arpanet in August 1974, carrying 16k CVSD encoded voice – first implementation of Voice over IP
• 1977: Danny Cohen, Vint Cerf, Jon Postel agree to separate IP from TCP, and create UDP for carrying real time traffic
• 1981: IPv4 is described in RFC 791.
• 1985: The National Science Foundation commissions the creation of NSFNET.
• 1986: Proposals from various standards organizations for Voice over ATM, in addition to commercial packet voice products from companies such as StrataCom
• 1992: Voice over Frame Relay standards development within Frame Relay Forum
• 1994: First Voice Over IP application (Freeware for Linux)
• 1995: VocalTec releases the first commercial Internet phone software.
  • Beginning in 1995, Intel, Microsoft and Radvision initiated standardization activities for VoIP communications system.
• 1996:
  • ITU-T begins development of standards for the transmission and signaling of voice communications over Internet Protocol networks with the H.323 standard.
  • US telecommunication companies petition the US Congress to ban Internet phone technology.
• 1997: Level 3 began development of its first softswitch, a term they coined in 1998.
• 1999:
  • The Session Initiation Protocol (SIP) specification RFC 2543 is released.
  • Mark Spencer of Digium develops the first open source private branch exchange (PBX) software (Asterisk).
• 2004: Commercial VoIP service providers proliferate.