The Internet seems to have just arrived, so how can we possibly imagine what will replace it? In truth, early versions of the Net have been around since the 1960s and '70s, but only after the mid-1990s did it begin to have a serious public impact. Since 1994, the population of users has grown from about 13 million to more than 300 million around the world. About half are in North America, and most--despite significant progress in rolling out high-speed access--still reach the Internet by way of the public telephone network.
What will the Internet be like 20 years from now?
Like the rest of infrastructure, the Internet will eventually seem to disappear by becoming ubiquitous. Most access will probably be via high-speed, low-power radio links. Most handheld, fixed and mobile appliances will be Internet enabled. This trend is already discernible in the form of Internet-enabled cell phones and personal digital assistants. Like the servants of centuries past, our household helpers will chatter with one another and with the outside help.
At some point, the armada of devices we strap to our bodies like tools on Batman's belt will coalesce into a smaller number of multifunction devices. Equipped with radio links, a pda can serve as an appliance-control remote, a digital wallet, a cell phone, an identity badge, an e-mail station, a digital book, a pager and perhaps even a digital camera. There is sure to be a catchy name for this all-purpose Internet-enabled thingy, perhaps Wireless Internet Digital Gadget for Electronic Transactions, or WIDGET.
So many appliances, vehicles and buildings will be online by 2020 that it seems likely there will be more things on the Internet than people. Internet-enabled cars and airplanes are coming online, and smart houses are being built every day. Eventually, programmable devices will become so cheap that we will embed them in the cardboard boxes into which we put other things for storage or shipping. These passive "computers" will be activated as they pass sensors and will be able to both emit and absorb information. Such innovations will facilitate increasingly automatic manufacturing, inventory control, shipping and distribution. Checkout at the grocery store will be fully automatic, as will payment via your digital wallet.
The advent of programmable, nanoscale machines (see "Will Tiny Robots Build Diamonds One Atom at a Time?" in this issue) will extend the Internet to things the size of molecules that can be injected under the skin, leading to Internet-enabled people. Such devices, together with Internet-enabled sensors embedded in clothing, will avoid a hospital stay for medical patients who would otherwise be there only for observation. The speech processor used today in cochlear implants for the hearing impaired could easily be connected to the Internet; listening to Internet radio could soon be a direct computer-to-brain experience!