The Internet Stream Protocol family was never introduced for public use, but many of the concepts available in ST are similar to later
Asynchronous Transfer Mode protocols and can be found in
Multiprotocol Label Switching (MPLS). They also presaged
voice over IP. ST arose as the transport protocol of the
Network Voice Protocol, a pioneering computer network protocol for transporting human speech over packetized communications networks, first implemented in December 1973 by Internet researcher
Danny Cohen of the
Information Sciences Institute (ISI) as part of
ARPA's Network Secure Communications (NSC) project. First specified in 1979, ST was envisioned as a connection-oriented complement to
IPv4, operating on the same level, but using a different header format from that used for IP datagrams. According to IEN-119, and published in 1995 as RFC 1819. ST2 distinguishes its own packets with an
Internet Protocol version number 5, although it was never known as IPv5. ==References==