ARPANET 50th Anniversary Marked at 2019 AAAS Annual Meeting

& THIS YEAR IS the fiftieth-year anniversary of the development and installation of the first four ARPANET Interface Message Processor (IMP) packet switches at the University of California Los Angeles (UCLA), Los Angeles, CA, USA; Stanford Research Institute (SRI), Menlo Park, CA; the University of California Santa Barbara (UCSB), Santa Barbara, CA; and the University of Utah, Salt Lake City, UT, USA (see front cover). The four-node network with its connections to an SDS Sigma 7 at UCLA, SDS-940 at SRI, IBM 360 at UCSB, and DEC PDP-10 at the University of Utah was a key early demonstration of the efficacy of packet switching technology. It led directly to the expansion of the ARPANET to dozens of IMPs andmany more application computers communicating with each other in various combinations. In turn, the ARPANET became one of the first internets, played a key role in the earliest internetworking experiments, and for a while was the core of the emerging Internet. It is not unreasonable to call the ARPANET the precursor of the Internet and an inspiration for an explosion in networking research and implementations. The American Association for the Advancement of Science held its annual meeting on February 14–17, 2019, at the Washington, DC, Marriott Wardman Park Hotel, and the program included three history sessions: 1) Nearly Double Platinum: 150 Years of the Periodic Table; 2) the Legacy of the Apollo Program; and 3) ARPANET 1969 to 2019: Celebrating 50 Years Since “LO”. The ARPANET session panel participants were Vint Cerf, Steve Crocker, Len Kleinrock, Bob Kahn, and Dave Walden (Figure 1). In 1969, Cerf and Crocker were graduate students at UCLA, working on Kleinrock’s U.S. Advanced Research Projects Agency (ARPA) research contract, where they participated in connecting the first computer to the first IMP. Kahn and Walden were part of Bolt Beranek and Newman’s initial seven-person team that Digital Object Identifier 10.1109/MAHC.2019.2913715