- Felisac
FiberMall
Answered on 8:44 am
The 100G-SWDM4 transceiver uses four wavelengths in the 850nm window, while the 100G-SRBD transceiver uses two wavelengths in the same window. This means that the 100G-SWDM4 transceiver has a higher spectral efficiency and can support more channels on the same fiber. However, the 100G-SRBD transceiver has a lower insertion loss and a higher tolerance to modal dispersion, which can improve the signal quality and reliability.
The 100G-SWDM4 transceiver can support up to 70m over OM3 MMF or up to 100m over OM4 MMF, while the 100G-SRBD transceiver can support up to 70m over OM3 MMF, up to 100m over OM4 MMF, or up to 150m over OM5 MMF. This means that the 100G-SRBD transceiver can extend the reach of 100G transmission over duplex MMF by using OM5 MMF, which is a new type of MMF that has a wider bandwidth and lower attenuation than OM4 MMF.
The 100G-SWDM4 transceiver is compatible with the QSFP28 form factor and LC connectors, while the 100G-SRBD transceiver is compatible with both QSFP28 and QSFP form factors and LC connectors. This means that the 100G-SRBD transceiver can support both 100G and 40G ports, while the 100G-SWDM4 transceiver can only support 100G ports. However, the QSFP28 form factor is more compact and power-efficient than the QSFP form factor, which can save space and energy in data centers.
Both the 100G-SWDM4 and 100G-SRBD (sometimes called a “BIDI” transceiver) have been widely deployed within the industry, and share the same optical reach and fiber type (70m/100m over OM3/OM4 duplex MMF).
However, the 100G-SWDM4 and 100G-SRBD do not interoperate with each other.
If interop with future 400G optics is a consideration, then the QSFP-100G-SRBD should be considered. The QSFP-100G-SRBD transceiver will interoperate with future Arista “400G-BIDI” transceivers. That is, an Arista OSFP-400G-SRBD or QDD-400G-SRBD transceiver will support breakout into 4x QSFP-100G-SRBD. The SWDM4 does not have a path for interop with future 400G optics.
The decision on which optic to will often depend on interop requirements. For example, for applications that require optical interop with third party 100G BIDI optics, the QSFP-100G-SRBD should be used.
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