Both the 100G-SWDM4 and the 100G-SRBD Transceivers Support 100G over Duplex Multi-Mode Fiber. When Should Each Transceiver Be Used

Both the 100G-SWDM4 and the 100G-SRBD Transceivers Support 100G over Duplex Multi-Mode Fiber. When Should Each Transceiver Be Used?

The 100G-SWDM4 transceiver uses four wavelengths in the 850nm window, while the 100G-SRBD transceiver uses two wavelengths in the same window.聽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 鈥淏IDI鈥澛爐ransceiver) 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 鈥?00G-BIDI鈥澛爐ransceivers.聽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.

FAQS

Q: 400G QSFP-DD vs 400G OSFP/CFP8: What are the differences?

A: The table below includes detailed comparisons for the three main form factors of 400G transceivers.

Q: How does the QSFP+ to SFP+ fiber convertor allow 4x 10G?

A: To enable 4x 10G connectivity, a QSFP+ to SFP+ fiber converter utilizes a breakout cable. This cable splits the 40G channel provided by the QSFP+ transceiver into four individual 10G channels, each connected to an SFP+ transceiver. Essentially, the converter breaks down the high-speed 40G signal into four separate 10G signals, allowing each SFP+ port to transmit data at 10G speeds. This configuration is beneficial for scenarios where equipment with SFP+ interfaces needs to communicate with a device equipped with a QSFP+ port, providing flexibility and compatibility in networking setups.

Q: What does “SR8”, “DR4”, “XDR4”, “FR4”, and “LR4” mean?

A: “SR” refers to short range, and “8” implies there are 8 optical channels. “DR” refers to 500m reach using single-mode fiber, and “4” implies there are 4 optical channels. “XDR4” is short for “eXtended reach DR4”. And “LR” refers to 10km reach using single-mode fiber.

Q: Can I plug an OSFP transceiver module into a QSFP-DD port?

A: No. QSFP-DD and OSFP are totally different form factors. For more information about QSFP-DD transceivers, you can refer to 400G QSFP-DD Transceiver Types Overview. You can use only one kind of form factor in the corresponding system. E.g., if you have an OSFP system, OSFP transceivers and cables must be used.

Q: What other breakout options are possible apart from using OSFP modules mentioned above?

A: OSFP 400G DACs & AOCs are possible for breakout 400G connections. See 400G Direct Attach Cables (DAC & AOC) Overview for more information about 400G DACs & AOCs.

Q1: What is the difference between QSFP28 ER4 and QSFP28 ER4 Lite Module?

A: The QSFP 100G ER4 has a series of BER requirements of better than 1E-12 without FEC optical modules. However, the receiving sensitivity of 100G QSFP28 ER4 is not satisfied with the existing APD technology. Therefore, many optical module manufacturers/suppliers defined a non-standard 100Gbase ER4 Lite module with a QSFP28 package where the largest transmission distance is up to 40km with FEC or 30km without FEC.?Walsun provides the QSFP28 100G ER4 Lite module compliant with the Ethernet 100Gbase ER4 Lite standard to meet the harshest external operating conditions including temperature, humidity, and EMI interference.

Q2: How does the QSFP 100G ER4 Module differ from the QSFP28 4WDM?

A: The QSFP 100G ER4 optical transceiver supports dual 100G Ethernet applications while the 100G QSFP28 4DWM only supports 100G Ethernet applications. The commons and differences are listed below.