Internet traffic continues to grow dramatically, with new data-heavy applications such as cloud-based services a significant factor contributing to this growth. In response, the number of data centers around the globe has grown, however, the demand for the network capacity offered by data centers exceeds their supply.
A Growing Demand for Data Centers
Data centers run applications and store and process massive amounts of data that pushes datacom technology to its limits. Computing related applications that challenge today’s data center network capacities include real-time data handling, artificial intelligence and machine learning, all playing an increasing role in the industrial environment. The move to more remote working environments has driven increased demand for service applications such as software as a service (SaaS), remote workplaces, and associated with it, video conferencing and collaboration software platforms. In the consumer segment, video streaming and video-on-demand services have become ubiquitous. Also, cloud storage access from mobile devices is used more frequently with faster mobile networks based on the 5G standard. Finally, data traffic within data centers also intensifies, as not only storage but also processing data becomes increasingly important supporting activities like big data analysis.
To handle the growth in datacom traffic, expansion of network capacities is necessary. The network capacity is the amount of data that can be transmitted in a data center in a given amount of time. It is also called the bandwidth of a network. Beyond creating more data centers, optimization of the bandwidth of a given network can be achieved by employing optical fiber interconnects.
From Single to Multi-Channel Fiber Networks
Data centers switched from copper cable to optical interconnects many years ago, leading to a large increase in capacity. Wavelength division multiplexing (WDM) is the technical approach which makes it possible to further increase the transfer bandwidth in optical networks. WDM enables transport of more than one optical data channel, each with a unique wavelength, to be sent through a single optical fiber cable at the same time, thus expanding the capacity of the network corresponding to the number of different wavelength channels that are multiplexed.
To implement multiplexing techniques, transceivers must be capable of generating and combining or separating optical signals at different wavelengths. Transceivers are the fundamental devices in optical datacom networks. These optical modules convert electrical signals into optical signals and vice versa.
Optical Tunability
Transceivers were first equipped with lasers emitting light at a single wavelength into an optical fiber. Tunable laser sources were the next logical step to implement multiplexing in optical networks. Most challenging in the integration of tunable lasers in transceiver modules was to keep a low power consumption while achieving small form factors that are compatible with the existing data center infrastructure, and on top of that, delivering high laser performance. Integrated tunable laser assemblies (ITLAs) were eventually developed to fulfill these requirements. The integration of tunable lasers into these modules would not have been possible without optical filters. Etalons and other filter solutions are essential components in multi-channel transceivers. They are vital for wavelength tuning and stabilization of the laser output wavelength. Precise wavelength control is needed in WDM, as a growing number of optical channels require smaller channel spacing and thus highly accurate tuning and filtering.
To further expand data center network capacities, multiplexing and thus tunable lasers are the most promising route in optical datacom. At Iridian we offer customized filter solutions including etalons for the development of future data center network components. We collaborate directly with our customers to tailor filter solutions addressing both technical and commercial requirements from initial samples to high-volume production.
