100G Single Lambda is an optical specification that uses PAM4 signaling (four-level pulse amplitude modulation) to transmit the 100G data stream via a single laser/wavelength. It is standardized for the first time by the 100G Lambda MSA (Multisource Agreement), an industrial consortium with a common focus to provide a new set of optical interface specifications. These specifications are based on an optical throughput of 100 Gb/s and aim to be used cheaply in 100G and 400G applications. The new 100G Single Lambda Standard not only reduces the complexity of optical components in modules, but also reduces the cost of 100G connections. According to IEEE, the ability to support 100G per lambda (wavelength) could reduce the cost of a 100G optical signal with a single optical channel by at least 40%. This means that switching from 4 wavelengths / Lambda to one wavelength / Lambda results in a relative cost reduction of more than 40%. Then comes the Transceiver Single Lambda 100G to simplify the structure of optical modules and improve efficiency. The 100G Single Lambda Transceiver includes 100GBASE-DR, 100GBASE-FR (100G-FR) and 100GBASE-LR (100G-LR). These transceivers support the host`s 4x 25G electrical signal and use a DSP to translate the signal into PAM4 modulation, instead of using NRZ signals, as is the case for LR4, CWDM4 or PSM4. Using the PAM4 signal on a single wavelength means that the entire 100G data stream is transmitted by a single laser without WDM or parallel fiber, reducing the number of optical components such as the transmitter and receiver from 4 to 1. The 100GBASE-DR is specified for 500m connections.
Subsequently, the 100G Lambda MSA extended the range to 2 km with 100GBASE-FR, which allowed for longer connections or environments with higher losses. So far, the MSA has extended the range from 100GBASE-LR to 10 km and addressed the same applications as 100GBASE-LR4. For more information about the 100G Lambda MSA group or to download the updated specifications, please visit the MSA www.100glambda.com website. This MSA is open to all interested persons who wish to join it. Companies are invited to join the consortium as contributor members. The appearance of 100G Single Lambda is no coincidence. Most optical transceivers such as 100GBASE-LR4, 100G-CWDM4, 100G-PSM4 and 100GBASE-SR4 today consist of four sets of transmitters and receivers operating in parallel 25Gb/s lanes. These four optical signals are either coupled by parallel fibers or for transport to a single multiplexed fiber, which requires a series of expensive optical components and packaging. In order to reduce total costs and improve transmission efficiency, a 100G single lambda transceiver specification was proposed. Transceiver with this specification use 100G PAM4 signaling for 100G per wavelength, which reduces optical complexity and costs by reducing the number of optical transmitters and receivers from 4 to 1.
“The rapid convergence of stakeholders and the technical agreement underscore the industry`s significant efforts and demand to bring this technology to market as quickly as possible,” said Mark Nowell, CO-CHAIR of MSA. As PAM4 modulation has enabled a one-lane 100G, upgrading from 100G to 4x 100G becomes a reality. For example, the IEEE 100GBASE-DR used for the optical standard 400GBASE-DR4. The 400GBASE-DR4 could escape into four parallel 100GBASE-DR modules and offer 400G connectivity of more than 500m. With the 100G single Lambda Transceivers, 100G connections are easy from a 400G port. On September 20, 2018, the 100G Lambda MSA group announced that MSA membership had grown from the original 22 promoters to 16 other contributors. The MSA has developed optical specifications for 100G and 400G that use 100G over a single wavelength to reduce costs. As vendors begin to recognize the growing advantage and dynamism in the 100G per Lambda solution market, companies are embracing the MSA.
Members of the 100G Lambda MSA group also announced the success of their private optical interoperability module.