SFP28 25Gb SR Optical Transceiver, HP Enterprise 845398-B21-RFB, 100 m reach

SFP28 25Gb SR Optical Transceiver, HP Enterprise 845398-B21-RFB, 100 m reach is a short-range multimode fiber transceiver module designed by HP Enterprise to provide hot-pluggable 25 Gigabit Ethernet connectivity. The module supports SR (short reach) 25Gb/s operation over multimode fiber with a nominal maximum reach of up to 100 meters, enabling low-latency links between servers, switches and other data-center or campus network equipment with compatible SFP28 ports.

Advantages

The HP Enterprise 845398-B21-RFB SFP28 transceiver offers compact SFP28 form factor compatibility for high-density racks and switch ports while supporting 25 Gb/s data rates for improved throughput compared with 10G links. Its short-range SR design is intended for multimode fiber deployments up to 100 m, providing predictable link behavior and low latency for east-west traffic inside racks and across adjacent equipment. The module is hot-pluggable for on-the-fly insertion or replacement without powering down compatible systems.

Suitable for

• Connecting 25G-capable servers to top-of-rack switches over multimode fiber
• High-density aggregation in data center racks and pod architectures
• Short-distance links in campus networks and equipment rooms (up to 100 m)
• Upgrading from 10G to 25G links where multimode fiber is deployed

Key specifications

• Brand: HP Enterprise
• Model / MPN: 845398-B21-RFB
• Form factor: SFP28
• Data rate: 25 Gb/s (SR)
• Fiber type: Multimode fiber (MMF)
• Nominal reach: up to 100 meters
• Hot-pluggable: Yes

How to use

Install the SFP28 transceiver into any compatible SFP28 port on supported HP Enterprise or compatible network equipment following the equipment manufacturer’s instructions. Ensure the multimode fiber patch cable and connectors match the transceiver’s interface, observe correct polarity for transmit/receive pairs, and secure fiber connections to avoid strain. After insertion, verify link status through the switch or server management interface and confirm the port is configured for 25 Gb/s operation if manual configuration is required.

Recommendations

Use multimode fiber rated for the required distances and maintain clean connectors to prevent signal degradation. For rack or data center deployments, document port mappings and verify compatibility with the host equipment firmware; keep spare transceivers for rapid replacement to minimize downtime.