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Scientists all over the world are working hard to curb the rapidly increasing energy consumption of the internet. But even the best efforts in the world are leaving us at just break even.

In 2020, the internet will connect more than 20 billion devices. Not only mobile devices and computers used by most of the world’s population, but also sensors and ’smart’ objects connected in the Internet of Things, which have caused a veritable data tsunami over the past few years. And this tsunami shows no sign of abating in the future.

Today, global data communication emits 2-3 per cent of all anthropogenic CO2. Furthermore, traffic is increasing by 25 per cent every year. If we continue with the same infrastructure as we have been using up to now, it won’t be long before the internet is the worst CO2-emitter on Earth.

“The internet is growing so explosively that if we were to do nothing, in 10 years the energy cost of running the internet would double the global carbon footprint,” says Associate Professor Martijn Heck from Aarhus University.

Therefore, he is working with several other researchers from Aarhus University on the three-year Grand Solutions project INCOM, which aims at forging energy-
efficient solutions for the dramatically increasing global data communication.

The object of INCOM is to turn a great many small knobs that each contribute directly or indirectly to a lower energy consumption for the internet, and with a large number of other national and international players, the project will find solutions for the next generation of communication infrastructure.

Among other things, the plan is to compress the total amount of sensor traffic significantly by using novel security and compression algorithms at the end user. At the same time, as another example, the number of light sources that operate the internet will be reduced, so that one laser can replace hundreds of lasers, which, in addition to significant energy savings, will also enable higher processing speeds.

The INCOM project consists of several large individual work packages, each with its own area. Martijn Heck is developing new chip-based laser systems based on existing integration technologies, and his colleagues, Associate Professor Qi Zhang and Associate Professor Rune Hylsberg Jacobsen, are working with wireless communication and security for IoT devices.

“IoT devices generate vast amount of data every second of every day. The ever-increasing data generated by all the sensors far exceeds all the storage on the planet. Sensors have been installed everywhere already, and we’ve really only just started on the wave of digitalisation. In my opinion, it’s not a sustainable solution to store all the data we collect. There’s no room for it. Massive sensor data is seriously stressing the global communications network infrastructure. We need smart solutions while expanding the network capacity,” says Associate Professor Qi Zhang.

With her work package, which is about developing a lightweight security system that is also scalable and energy-efficient, Associate Professor Zhang expects to be able to cut away up to 90 per cent of all data traffic, and clearly this will ultimately have a huge impact on internet energy consumption:

“In our project, we’re compressing and encrypting the data simultaneously and with very low complexity. We can compress the data to only 10 or 20 per cent of its original size, and that could have a huge influence on the storage and traffic needed – both in the access networks but also in the core network,” she says.

The traffic hubs in the information age are data centres connected by intercontinental optical cables that transmit information at high speed from machine to machine and from person to person. Half of the world’s population has become connected to the internet in just 30 years.

More people and more devices will obviously require better infrastructure. However, it is unlikely that many of us realise that even simple searches on the internet require relatively large amounts of data exchange and power consumption.

“When you send one bit of data into a data centre, there’s a factor of 10 or 100 more bits going around inside the data centre. And for every server inside the data centre, that data is again multiplied by a factor of 10 or more. And every server has a processor and a memory where more factors are added. Tens of thousands of bits are exchanged for every single bit going into the data centre, and that requires a huge amount of energy. A simple Google search, for example, triggers a large number of internal processes, which is very energy intensive,” says Martijn Heck.

Therefore, the project is basically not to make the internet greener, he explains:

“All the newer data centres out there have 40 Gb/s connections to the servers. The newest top 1 per cent have 100 Gb/s, moving into 200 Gb/s. In two to three years, the standard will be 400 Gb/s, and in five to seven years from now we’ll have 1 Tb/s. When you talk about Moore’s Law in electronics, you have the exact similar growth in communications. The point is that what we do this year with 100 Gb/s, we have to do next year for 200 Gb/s at the same cost and the same energy consumption. Not the same energy consumption per bit but the same overall energy consumption,” he says and continues:

“INCOM is not going to make the internet any greener whatsoever. It will make the internet greener per bit, but not in total. In this project, we’re working hard just to prevent the whole thing from blowing up. We’re just trying to tame the beast a bit – but the beast is still there and it’s getting more and more furious by the minute. The best we can do is break even. And if we do break even, we’re still doing the best job in the world.”