The amount of data generated every second across the globe is vast and continues to grow rapidly, says Ciena's Azz-Eddine Mansouri.
Cumulatively, users are already spending 114,000 years’ worth of time on YouTube every single day. With connected devices and IoT becoming ever more prolific, current projections indicate that interconnect bandwidth will grow up to 5,000 Tb/s, with double-digit growth rates across multiple industry segments from cloud and IT to healthcare and energy by 2020.
To be able to cope with these huge data requirements, operators need to be able to transport more data, quicker and with lower latency. For the most part, physical fibre infrastructure is fixed and therefore the ability to add more physical transportation channels is prohibited. Therefore, the only viable solution is to increase the amount of data that can be transported on a single optical wavelength.
As a result, network operators are increasingly looking to advanced optical transmission technologies and 400G to connect between data centres and other congested parts of their core and metro networks.
Revolutionising optical network transport
Coherent technology uses digital signal processing to remove linear noise from the channel. This technique effectively broke through the 10Gb/s optical transmission barrier and allowed higher optical transmission speeds. Since the cost of optical technology scales linearly with the number of wavelengths, increasing the speed of a single wavelength drops the cost per bit for transmission. With such ongoing technological advancements, coherent technology has enabled reduction in cost/bit per year by 30 percent.
400G is facilitating significant changes in today’s networks, enabling faster, more effective data transfers between metro data centres and alleviating congestion across the network. These next-generation coherent optical solutions support 400G of capacity on a single wavelength, meaning that 400 billion bits of information can now travel down a single optical wavelength every second. In context, that’s equivalent to over 180,000 simultaneous HD video streams, or more than 70,000 songs downloaded in a single second. In fact, 400G wavelengths could even support up to 80,000 Fortnite (the online game popular around the world) players, on a single network link.
To make single-wavelength 400G a reality, it was necessary to realise two key technological advancements:
• The first involves the ability to operate at a higher symbol rate (also known as baud). Whereas previous generation coherent systems operate at 32-35 GBaud, the new generation will be capable of operating at 56 GBaud or higher, which means it can process more symbols per second. A symbol, composed of a number of zeros and/or ones, represents the bits of information transmitted over a fibre.
• The second involves using modulation schemes with more dense constellations, or more bits per symbol.
To increase the performance of 400G, Ciena has designed its WaveLogic AI solution to take these advanced coherent modulation formats a step further. 400G is realised using a performance-optimised 32-QAM modulation scheme, where advanced coding techniques are used to shape the constellation to achieve maximum performance.
What does this all mean for network providers? With 400G solutions, customers can more effectively scale their networks, to achieve greater capacity and carry more data, whilst lowering capital expenditure, footprint and energy consumption in data centres. They can also create networks that are more intelligent and programmable – meaning they can adapt to changing traffic demands and network requirements.
The road to 400G
The incentive for operators to implement 400G is clear. Despite the difficulty in predicting the next ‘killer app’ and how future data demands will inflict strain upon existing networks, there is a clear data growth trend in the region that will be fueled by activities such as new 5G network rollouts, IoT, Smart Cities and Dubai Expo 2020 as well as a young and vibrant population. The current pace of technology innovation strongly suggests that data usage will only keep going up, and the ability to scale networks effectively will be important in preparing to meet rising and dynamic data demand.
As we embark upon the next phase of advancement in optical networking, it will be exciting to see how the benefits offered by 400G influence the market and enable the adoption of new connected technologies and digital services that will help create positive changes to the quality of life for both businesses and consumers in the future.