A milestone occurred in October 1977, when Cerf and Kahn and a dozen or so others demonstrated the first three-network system with packet radio, the ARPANET, and SATNET, all functioning in concert. Messages traveled from the San Francisco Bay area through a packet-radio net, then the ARPANET, and then a dedicated satellite link to London, back across the packet-satellite network and across the ARPANET again, and finally to the University of Southern California’s Information Sciences Institute (ISI) in Marina del Rey. The packets traveled 94,000 miles without dropping a single bit.
