|MadSci Network: Computer Science|
I'm going to answer your questions out of order. First, let me address the "big picture" question about the future of wireless:
Your concern about the extraordinary bandwidth requirements of a universal Internet are accurate, albeit somewhat vague. Artificial intelligence (AI) and virtual reality (VR) are still very much in their infancy and at least two or three decades away from commercial maturity and everyday use. No one can say with any degree of certainty what the exact infrastructure requirements of a Gibsonesque "cyberspace" will be.
But consider how much you really want the network to do. Does it make sense to send lots of data around when you could replicate it locally and do periodic updates, as some offline web browsers do? And how much data do you really need to send across the network? A well-designed application will not overtax the network, regardless of the available bandwidth. The likely scenario is that online AI and VR applications will become more sophisticated as the network grows, much as the World Wide Web has grown over time.
To my knowledge, nobody claims that wireless telecommunications will completely replace wired communications at any point in our future. If we confine our discussion to the planet Earth, wired communication systems will always be more robust than wireless. Compare the picture quality of cable TV to broadcast TV, for example. Wireless is essentially limited to line-of-sight transmission method and susceptible to open-air interference, of which there is more and more every day. There will be applications where wireless is preferred, and other applications where wired is preferred.
It's the same principle as physical transportation-- you use the transit method most suited to the distance you need to travel. If you're going to your neighbor's house, you walk instead of driving your car. If you're going from Los Angeles to New York, you take an airplane instead of driving. In the telecommunications world, the carriers are different-- coaxial cable, fiber optic cable, and Earth-orbiting satellites, among others-- but the rationale remains the same. You don't bounce a local telephone call off a satellite because it's faster, cheaper, and more reliable to use the ground wires.
Unless an epochal technology breakthrough occurs, the network of the future will be a combination of wired and wireless.
And now to your specific concerns about wireless technology:
Assuming that our discussion is limited to electromagnetic signals, no mode of wireless communication can ever be interference-free. Because you have no control over the medium through which your signal travels, you can't prevent interaction with other signals. If the environment changes (e.g., bad weather, walking into a building), your signal is affected.
Think about sunlight, the wireless signal that the Sun continuously transmits to the Earth. If something moves between you (the Earth) and the transmission source (the Sun), it interferes with that signal by blocking it, and without removing the obstacle, there's no foolproof way to recover the original signal. The best you can do is to use digital encoding to detect when a transmission has been tampered with.
The problem of cellular and cordless phones interfering with each other is well documented. Digital signalling methods are helping to alleviate this, since better error checking and correction are possible, and also offer greater security. In fact, engineering will provide near-term solutions to almost all these problems. And who knows what new technology might appear in the future?
But there is one problem which can't be engineered away. As a recent paper from the University of Zurich's Department of Computer Science says: "true global communications rely on global communications standards." The greatest technology in the world is worthless if no one can use it.
Hope this helps!
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