The processor will accelerate the optics to 800 Gb / s: how it works

    Telecommunications equipment developer Ciena introduced an optical signal processing system. It will increase the data transfer speed in fiber optic up to 800 Gb / s. Photos - Timwether - CC BY-SA Under the cut - about the principles of its work.

    Need more fiber

    With the launch of a new generation of networks and the spread of Internet of things devices - according to some estimates, their number will reach 50 billion in three years - the volume of world traffic will only increase. Deloitte says that the existing fiber-optic infrastructure, which is the basis for 5G networks, is not enough for such a load. The view of the analytical agency is supported by telecommunications companies and cloud providers.

    To remedy the situation, more and more organizations are working on systems that increase the bandwidth of the “optics”. One of the hardware solutions was developed at Ciena - it was called WaveLogic 5. According to the company's engineers, the new processor is capable of providing data transfer rates up to 800 Gb / s at a single wavelength.

    How the new solution works

    Ciena introduced two modifications of the WaveLogic 5 processor. The first is called WaveLogic 5 Extreme. It is an ASIC that acts as a digital signal processor ( DSP ) of a fiber optic network. DSP converts the signal from electrical to optical and vice versa.

    WaveLogic 5 Extreme supports fiber bandwidth from 200 to 800 Gb / s - depending on the distance you want to send the signal to. For more efficient data transmission, Ciena introduced probabilistic constellation shaping (PCS) algorithm into the processor firmware .

    This constellation is a set of amplitude values ​​(points) for the transmitted signals. For each of the constellation points, the PCS algorithm calculates the probability of data distortion and the value of the energy required to send the signal. After that, he chooses the amplitude for which the signal-to-noise ratio and energy consumption will be minimal.

    The processor also uses the forward error correction algorithm ( FEC ) and frequency division multiplexing ( FDM ) signal . To protect the transmitted information, the AES-256 encryption algorithm is used .

    The second modification of WaveLogic 5 is a series of Nano plug-in optical modules. They can send and receive data at speeds up to 400 Gbit / s. Modules have two form factors - QSFP-DD and CFP2-DCO. The first is small and designed for 200 or 400GbE networks. Due to the high connection speed and low power consumption, QSFP-DD are suitable for data center solutions. The second form factor - CFP2-DCO - is used to send data over distances of hundreds of kilometers, so it will be used in 5G networks and the infrastructure of Internet providers.

    The WaveLogic 5 will go on sale in the second half of 2019.

    Photo - PxHere - PD

    Advantages and disadvantages of the processor

    WaveLogic 5 Extreme was one of the first processors on the market that transmits data at the same wavelength at a speed of 800 Gb / s. For many competitive solutions, this figure is 500-600 Gbit / s. Ciena has the advantage of expanding the optical channel capacity by 50% and increasing its spectral efficiency by 20%.

    But there is one difficulty - with signal compression and increasing the data transfer rate, there is a risk of information distortion. It increases with increasing distance. For this reason, the processor may have difficulty sending a signal over long distances. Although the developers say that WaveLogic 5 is capable of transmitting data “across the oceans” at a speed of 400 Gbit / s.


    Systems for increasing fiber throughput are also being developed by Infinite and Acacia. The solution of the first company is called ICE6 (ICE - Infinite Capacity Engine). It consists of two components - an optical integrated circuit (PIC - Photonic Integrated Circuit) and a digital signal processor in the form of an ASIC chip. PIC in networks converts a signal from optical to electrical and vice versa, and ASIC is responsible for its multiplexing.

    ICE6 Feature - Pulse shaping) A digital processor divides light of a certain wavelength into additional subcarrier frequencies, which expands the number of available levels and increases the spectral density of the signal. It is expected that ICE6, like WaveLogic, will provide data transfer speed in one channel at the level of 800 Gb / s. The product should go on sale by the end of 2019.

    As for Acacia, its engineers created the AC1200 module. It will provide a data transfer rate of 600 Gbit / s. This speed is achieved using the 3D-formation of the signal constellation: the algorithms in the module automatically change the frequency of use of points and their position in the constellation, adjusting the bandwidth of the channels.

    It is expected that new hardware solutions will increase the bandwidth of the optical fiber not only at distances within the same city or region, but also at more significant distances. To do this, engineers have to overcome the difficulties associated with channel noise. The increase in the capacity of submarine networks will positively affect the quality of services of IaaS providers and large IT companies, given that they “ generate ” half of the traffic transmitted across the ocean floor.

    What interesting things do we have on the ITGLOBAL.COM blog:

    Also popular now: