Technology has dramatically altered the world we live in. Network technologies in particular have played a central role in shaping the economies and societies of the twenty-first century.
One of the most important innovations in networking was, of course, the creation of the Internet—which allowed us to connect physical hosts anywhere and everywhere on the planet to each other. Once network operators were able to interconnect to each other using IP and other Internet standards, every available physical host was at least potentially available to every other physical host and to every authorized user.
