HPE 720187-B21 40GbE QSFP+ MPO SR4 Multimode Transceiver
Overview
The HPE 720187-B21 is a 40 Gigabit QSFP+ short-reach transceiver designed for high-density data center and enterprise core switching environments. Operating at 850nm over an MPO connector interface, it delivers SR4 parallel optics across four 10G lanes to achieve 40GbE throughput at distances up to 100 meters over OM3/OM4 multimode fiber — enough reach for most in-rack and cross-row structured cabling runs without needing longer-reach optics. If you're consolidating 10GbE uplinks or building out a 40G spine-leaf fabric, this form factor fits QSFP+ slots directly without breakout adapters.
Compatibility
The 720187-B21 is designed for HPE BladeSystem c-Class infrastructure — specifically HPE BLC (BladeSystem c-Class) switches and interconnect modules that accept QSFP+ transceivers. Verify your specific interconnect module's transceiver compatibility matrix before ordering, as HPE FlexFabric and Virtual Connect modules vary in their supported optic SKUs. The MPO interface requires a pre-terminated MPO trunk cable or MPO-to-LC fan-out on the far end; standard LC-duplex patch cables will not mate without an MPO cassette or adapter.
Installation Notes
SR4 parallel optics require MPO-12 or MPO-8 terminated multimode fiber (OM3 for 40GbE at 100m, OM4 extends headroom). Polarity matters: MPO connectors must follow Method B or Method A depending on your patch panel layout — confirm polarity before pulling cable. Clean MPO ferrules before insertion; particulate contamination on a 12-fiber MPO face degrades all four lanes simultaneously, which is harder to diagnose than a single LC fault. Do not exceed the 100m reach specification on OM3; signal integrity degrades sharply beyond rated distance on SR4 parallel optics.
