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The Bandwidth to Feel

For some years now, Internet2, a nonprofit advanced networking consortium in the United States, has been developing designing a new network intended to open up large amounts of dedicated bandwidth as required.

The reason for this is simple: The old, military-designed system we use now, the descendant of Arpanet, is designed for robustness above all else. It was designed to survive a war.

The system is based round the IP or Internet Protocol packet system. IP. The building block of every transmission protocol, breaks data into packets that are sent through the cables and conduits, broadcast over wireless networks and from satellites. Each packet is given a number and a transmission time. This is because the system works on the hope that all packets will reach their ultimate destination in order, but in practice this rarely happens. With each packet potentially taking a different route, frequently they arrive out of order, and there is a pause whilst they are reassembled.

With an email, this does not matter, nor with a film - that is what buffering is there for, as a defence against packet delay. However, when the signal is direct physical contact with another person via remote telehaptics, the delays do matter, as they chop and break up the signal. You could be shaking hands one minute, then your sense of touch essentially freeze for a minute or so whilst the next parcel of information comes down the line - 70 others are already waiting, but you're missing the information about a down stroke. Without it, other positional information will not make much sense.

The reason packets get delayed, is down to the routers, the boxes that sit on network junction points, and sort through the flood of incoming and outgoing packets. They have to fit them down a finite number of lines, each with specific limitations on how much data they can carry. The routers have to make judgement calls and prioritize traffic. If one line backs up, they send packets off on another, which might be longer, but will probably get to the destination more swiftly. Packets can actually end up going back the way they came in some cases, to try a different route to their destination.

Using this approach, full VR would never be possible. Just too many thousands of packets for different senses, all moving at once. You would literally come apart at the seams.

When pressed on Internet 2, Rick Summerhill, CTO stated on their efforts "The idea here is to basically look at the network in a different way."

Summerhill says that, using the dynamic circuit network, a researcher could set up a temporary connection to another location that would work like a phone call: the user's data would be carried directly to that other location, uninterrupted by the traffic of others sharing the network. The result is that large quantities of information could be transferred quickly and clearly.

The dynamic circuit network is really an enhancement of a traditional network, rather than a replacement. Internet2 still has a backbone that uses the standard IP common across the Web.

What makes the dynamic circuit network different is that it uses a circuit-switched network, which can be set up so that all the packets have to follow the same path. Also, those circuits don't have to be in place permanently, allowing a network that dynamically changes according to load, whilst still providing the minimum latency possible, but not requiring all new cabling laid in order to function.

Summerhill says that the dynamic circuit network is still in its early stages, and "still has some evolution to do." He recalls the time that IP wasn't considered ready for commercial applications.

It is still relegated solely to use by academia, but development and refinement continues. Eventually, it will replace Arpanet's way of doing business, and help usher in full sensory immersion.

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