Overview
The Twin-port transceiver is a key innovation for expanding the 400GbE Spectrum-4 Ethernet switch capabilities. The line rate is 400GbE Ethernet based on the 100G-PAM4 modulation. The switches use Twin port OSFP cages supporting two transceiver engines in a single OSFP form-factor plug creating 800Gb/s electrical to the switch and 2x400G optics using two MPO/-12/APC optical connectors.
Twin-port devices enable several unique configurations to connect switches together, and to adapters and DPUs. Switches maintain separate protocols.
The Twin-ports enable several unique configurations to connect switches to switches, ConnectX-7 adapters and BlueField-3 DPUs.
The Twin port OSFP uses two, 4-channel MPO-12/APC optical connectors with two 4-channel fiber cables. These can link to single port 400G OSFP or QSFP112 form-factor transceivers used in ConnectX-7 adapters and/or BlueField-3 DPUs.
The electronics, optics and optical connectors are the same for both single port OSFP and QSFP112 form-factors. Both ConnectX-7 and BlueField-3 devices can be used with Twin port OSFP transceivers at the same time with their respective form-factor type.
Twin-port single mode OSFP transceivers remain at 17 Watts for all configurations linking OSFP switches, OSFP and QSFP112 adapters, and DPUs simultaneously.
Linking Twin-port transceivers with 1:2 fiber splitter cables to 400G transceivers automatically creates 200Gb/s transceivers by activating only 2-channels and automatically reduces power consumption in the 400G transceiver from 9 to 6.5 Watts.
Twin-Port transceivers require ordering two fibers at specific lengths required
Each fiber cable can each be different lengths. Both fibers need to be same type: both straight or both splitters and not mixed.
Both fibers should be the approximately same length to avoid inducing different latency delays in the fibers (4.5ns/meter).
Straight and splitter fibers cannot be used at the same time in Twin port OSFP transceivers.
The combinations of Twin port 2x400G OSFP, 400G single port OSFP/QSFP112, ConnectX-7 and BlueField-3 all contain Ethernet protocols. This enables one set of cables, transceivers, adapters and DPUs to have multiple uses in a network – especially in Ethernet switching systems for storage and cluster communication.
The use cases include:
Switch-to-switch at 800Gb/s or to two switches at 400Gb/s
Switch-to-two combinations of 400G ConnectX-7 and/or BlueField-3
Switch-to-four combinations of 200G ConnectX-7 and/or BlueField-3