Boosting the funnel

September 10, 2010 in Adrian's tech blog


It was reported this week that a group of British scientists at Southampton University have developed a technique for keeping the light in -optic cables nice and tidy and in sync. I thought I’d write a short blog on it because the importance of the discovery seems have been missed by some commentators.

For my purposes, the is like a giant funnel; lots of stuff poured in the top at ever higher rates into narrower and narrower pipes the further we get from home. Funnel

We are now pouring more in the top than ever before, which means we need to make sure the neck of the funnel doesn’t become the problem.

One solution is to use a leaky bucket – the genuine name given to the techniques which lie behind many of the traffic shaping tools– but that doesn’t solve the problem, it merely optimises the experience for services squeezed by the neck of the funnel (not that its necessarily a bad thing either).

Increasing bandwidth over short distances is easy but extending over long distance is more problematic; we saw this in first generation and laser light is no different. But, and this a big but, as we move towards next generation access networks, with  the speeds already being deployed around Europe, the pressure on long haul inter-city and inter-national links will become immense. Delivering 100 Gbps is challenging over transatlantic distances and that’s only a hundred customers with gigabit watching quad-hd 3d movies.

If we reach in the home then rest assured the core will soon need . Delivering such bandwidth over 10’s of kilometres can be demonstrated but not over 100’s or 1,000′s – not in a single channel of usable bandwidth.

And here’s the problem. Fibre-optic cables are now so fine there isn’t much room for a beam of light to bounce off the wall of the fibre; so much so that over relatively short distances the effect is tiny and the signal emerges at the far end unscathed – but over long distances even small levels of bouncing around add up, corrupting the signal.

The developments announced this week are aimed at correcting the bouncing and corruption over distance, paving the way for terabit speeds across the ocean so our gigabit connected homes can still watch Hollywood/Bollywood films on our new  42” quad-hd 3d tv’s.

The whole space of photonics – the boundary where electronics meets light – is one which will move centre stage as we try to manage the funnel. Delivering high speeds to people’s homes is technically easy but ensuring there is the intelligence and scale in the rest of the network to match will frame the problem. Visionaries, like the people at Southampton University and others like InTune Networks and their work on switching tuneable lasers, may not make good dinner party talk but they will be the people that ensure the future Internet keeps up with the uses imagination puts it to.