What are “100G Lambda” Optics?

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Harry Collins

Answered on 8:05 am

100G Lambda Optics is an optical transceiver transmitting 100 gigabits per second (Gbps) of data over a single wavelength or lambda. They use a modulation technique called PAM4, which stands for Pulse Amplitude Modulation 4, to encode two bits of information per symbol. This allows them to achieve higher data rates than traditional NRZ (Non-Return-to-Zero) modulation, which encodes one bit per symbol.

100G Lambda Optics are compatible with 200G and 400G Ethernet standards, which use multiple lanes of 100G signals to achieve higher bandwidth. They can also interoperate with other 100G optics that use different modulation schemes or wavelengths, such as 100G DR (Duplex Reach), 100G FR (Four Wavelengths), or 100G LR4 (Long Reach). They can support various distances and applications, depending on the type and model of the transceiver.

  • QSFP-100G-DR: 100GBASE-DR single lambda QSFP, up to 500m over duplex SMF.
  • QSFP-100G-FR: 100GBASE-FR single lambda QSFP, up to 2km over duplex SMF.
  • QSFP-100G-LR: 100GBASE-LR single lambda QSFP, up to 10km over duplex SMF.

legacy 100g optics

100g single lambda optics

Some of the benefits of 100G Lambda Optics are:

They reduce the complexity and cost of the optical modules and the fiber infrastructure, as they use fewer components and wavelengths than other 100G optics.

They enable future-proofing and scalability of the network, as they can be reused or upgraded to new form factors or higher data rates without sacrificing performance or compatibility.

They provide operational flexibility and efficiency for data center operators, as they can connect to different types of devices and networks using the same type of optic.

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