What are the 100G-DR, 100G-FR and 100G-LR QSFP Transceivers?

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Harry Collins

Answered on 2:21 am

The 100G-DR, 100G-FR, and 100G-LR QSFP transceivers are optical modules that support 100 Gigabit Ethernet data rates over single-mode fiber. They are based on the IEEE 802.3 standard and the 100G Lambda MSA specifications. They use a single wavelength of light to transmit and receive data, which reduces the complexity and cost of the optical components. They also have a small form factor and low power consumption, making them suitable for high-density and low-power applications.

The main differences between the three types of transceivers are the reach and the interoperability with other modules. The 100G-DR transceiver supports a reach of up to 500 meters over duplex single-mode fiber and can interoperate with 400G DR4 modules in 4x100GbE breakout applications. The 100G-FR transceiver supports a reach of up to 2 kilometers over duplex single-mode fiber and can interoperate with 400G DR4+ modules in 4x100GbE breakout applications. The 100G-LR transceiver supports a reach of up to 10 kilometers over duplex single-mode fiber and can interoperate with 4x100G LR1 modules in 4x100GbE breakout applications.

The difference between a legacy 100G QSFP module and a 100G-DR / FR module is illustrated below.

legacy module and dr

The 100G-DR/FR/LR modules have a reach of 500m/2km/10km over SMF, and are designed to interoperate with 400G-DR4/XDR4/PLR4 transceivers using a breakout cable. Each 400G-DR4/XDR4/PLR4 module can connect to 4 x 100G-DR/FR/LR modules.

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