- Brian
John Doe
Answered on 7:32 am
In general, the letters refer to reach or optics technology, and the number refers to the number of optical channels:
SR8: Short Range 8. This transceiver supports 400G transmission over multimode fiber (MMF) with a maximum reach of 100 meters. It uses a MPO-16 connector and PAM4 modulation.
SR8-C: Short Range 8 Copper. This transceiver supports 400G transmission over copper cable with a maximum reach of 3 meters. It uses a QSFP-DD connector and PAM4 modulation.
SRBD: Short Range Bidirectional. This transceiver supports 400G transmission over MMF with a maximum reach of 70 meters. It uses a duplex LC connector and PAM4 modulation.
SR4: Short Range 4. This transceiver supports 400G transmission over MMF with a maximum reach of 100 meters. It uses a MPO-12 connector and PAM4 modulation.
DR4 / XDR4 / PLR4: Data Center Reach 4 / eXtended Data Center Reach 4 / Parallel Long Reach 4. These transceivers support 400G transmission over single-mode fiber (SMF) with a maximum reach of 500 meters / 2 kilometers / 10 kilometers respectively. They use a MPO-12 connector and PAM4 modulation.
FR4 / LR4: Fiber Reach 4 / Long Reach 4. These transceivers support 400G transmission over SMF with a maximum reach of 2 kilometers / 10 kilometers respectively. They use a duplex LC connector and PAM4 modulation.
2FR4: Two Fiber Reach 4. This transceiver supports 400G transmission over SMF with a maximum reach of 2 kilometers. It uses two duplex LC connectors and coherent modulation.
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