How can I Break Out a 400G Port and Connect to 100G QSFP Ports on Existing Platforms?

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FiberMall

Answered on 7:27 am

There are a few different ways to do this (as discussed earlier in this document), summarized below.

i) OSFP-400G-DR4 (or QDD-400G-DR4) to 4 x QSFP-100G-DR over 500m SMF

Connect up to 4 x QSFP-100G-DRs to a single OSFP-400G-DR4 (or QDD-400G-DR4). The QSFP-100G-DR can plug into any Arista 100G QSFP port.

OSFP-400G-DR4 (or QDD-400G-DR4) to 4 x QSFP-100G-DR over 500m SMF

ii) OSFP-400G-XDR4 (or QDD-400G-XDR4) to 4 x QSFP-100G-FR over 2km SMF

Connect up to 4 x QSFP-100G-FRs to a single OSFP-400G-XDR4 (or QDD-400G-XDR4). The QSFP-100G-FR can plug into any Arista 100G QSFP port.

OSFP-400G-XDR4 (or QDD-400G-XDR4) to 4 x QSFP-100G-FR over 2km SMF

iii) OSFP-400G-PLR4 (or QDD-400G-PLR4) to 4 x QSFP-100G-LR over 10km SMF

Connect up to 4x QSFP-100G-LRs to a single OSFP-400G-PLR4 (or QDD-400G-PLR4). The QSFP-100G-LR can plug into any Arista 100G QSFP port.

OSFP-400G-PLR4 (or QDD-400G-PLR4) to 4 x QSFP-100G-LR over 10km SMF

iv) H-O400-4Q100-xM (or H-D400-4Q100) to 4x QSFP100 ports with Active Copper DACs, 1m-5m

Connect up to 4x 100G QSFP ports to a single 400G OSFP or QSFP-DD port. The QSFP end of the active breakout DAC includes a gearbox chip that converts 2x50G PAM-4 electrical signals into a 4x 25G NRZ interface, the modulation format used in legacy 100G QSFP ports.

H-O400-4Q100-xM (or H-D400-4Q100) to 4x QSFP100 ports with Active Copper DACs, 1m – 5m.

v) OSFP-400G-2FR4 to 2 x QSFP-100G-CWDM4 over 2km SMF

If an OSFP port is configured for 2 x 100G (i.e. 200G total bandwidth), the OSFP-400G-2FR4 module can be used to connect to 2 x QSFP-100G-CWDM4 transceivers over duplex single-mode fibers.

Configuring an OSFP port for 200G total bandwidth means each of the 8 electrical lanes to/from the OSFP operates at 25Gb/s NRZ, the same modulation format used in legacy 100G QSFP ports.

OSFP-400G-2FR4 to 2 x QSFP-100G-CWDM4 over 2km SMF

vi) OSFP-400G-SRBD (or QDD-400G-SRBD) to 4x QSFP-100G-SRBD or 4x 100G-SR1.2 QSFPs over 100m MMF

Connect up to 4x QSFP-100G-SRBD, or 4x 100G-SR1.2 QSFPs to a single 400G-BIDI module.

OSFP-400G-SRBD (or QDD-400G-SRBD) to 4x QSFP-100G-SRBD or 4x 100G-SR1.2 QSFPs over 100m MMF

vii) OSFP-400G-SR8 (or QDD-400G-SR8) to 2 x QSFP-100G-SR4 QSFPs over 100m MMF

If an OSFP port is run at 200G total bandwidth, the OSFP-400G-SR8 module can be used to connect to 2 x QSFP-100G-SR4 transceivers using a multimode breakout cable.

OSFP-400G-SR8 (or QDD-400G-SR8) to 2 x QSFP-100G-SR4 QSFPs over 100m MMF

viii) Passive DAC breakout cable using CAB-O-2Q-400G-xM / CAB-O-2Q-200G-xM or CAB-D-2Q-400G-xM / CAB-D-2Q-200G-xM

If the OSFP or QSFP-DD port is run at 200G total bandwidth, a passive DAC breakout cable can be used to connect an OSFP or QSFP-DD port into 2x 100G QSFP ports.

Passive DAC breakout cable

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