Network QSFP+ Transceiver BlueOptics BO25K859S2D 40GBASE-SR4 Multimode Fiber

BlueOptics BO25K859S2D is a QSFP+ 40GBASE-SR4 multimode fiber transceiver designed for short-reach 40 Gbps links in data centers and high-density network environments. The module uses the QSFP+ form factor and is compatible with OM3 and OM4 multimode fiber, delivering four parallel 10 Gbps lanes for aggregate 40 Gbps connectivity. It is intended for server uplinks, switch-to-switch connections and aggregation links where reliable multimode transmission and compact, hot-pluggable installation are required.

Advantages

The transceiver offers compact QSFP+ packaging that maximizes port density while supporting 40 Gbps multimode transmission over short distances. Compatibility with OM3 and OM4 multimode fiber enables flexible deployment in existing multimode cabling plants. Hot-pluggable design simplifies installation and replacement without downtime for powered equipment. The module’s parallel-lane approach ensures efficient use of fiber infrastructure and predictable performance for bursty or sustained 40 Gbps traffic.

Suitable for

• Data center uplinks between servers and top-of-rack switches
• Switch-to-switch aggregation and spine-leaf interconnects
• Short-reach backbone links within campus or enterprise buildings
• High-density switch ports where space and port count are critical

Key specifications

• Form factor: QSFP+
• Data rate: 40 Gbps aggregate (4×10 Gbps lanes)
• Optical mode: Multimode fiber (OM3 / OM4 compatible)
• Standard: 40GBASE-SR4
• Reach: short-reach multimode links (dependent on fiber grade and link loss)
• Interface: MPO/MTP parallel fiber connector (4-lane parallel optics)
• Hot-pluggable QSFP+ module for easy installation

How to use

Install the QSFP+ transceiver into the QSFP+ port of a compatible switch, router or network interface card following the equipment manufacturer’s insertion instructions. Connect an MPO/MTP multimode trunk cable terminated for SR4 parallel optics to the module and route fiber to the corresponding SR4 module or breakout cassette on the far end. Ensure fiber grade (OM3 or OM4) and patching meet required link loss and distance expectations. After insertion, verify link status and adjust switch interface settings as needed for 40G operation.

Usage recommendations

Use OM3 for typical short-reach deployments and OM4 for extended short-reach distances or where future higher-margin performance is desired. Maintain clean MPO/MTP connectors and follow vendor guidance for fiber polishing and cleaning to ensure optimal signal quality. Confirm compatibility with the host equipment and perform link validation after installation.