HPE Aruba 845398-B21 Compatible 25G SFP28 SR Transceiver Module
This HPE Aruba 845398-B21 compatible transceiver provides 25G connectivity in a hot-swappable SFP28 package. Its optical design operates at 850nm for up to 100m on OM4 / 70m on OM3, using Duplex LC. Complete parameters and related OEM references help field technicians install, maintain and identify the exact compatible module.
OEM Part Number: 845398-B21HT Part Number: SFP-25GSR-85
Product Highlights
- Compatible alternative to HPE Aruba 845398-B21
- 25G connectivity at 25.78Gbps
- Optical wavelength: 850nm
- Specified reach: 100m on OM4 / 70m on OM3
- Duplex LC / MMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: 0 to 70°C (32 to 158°F)
Specifications
| HPE Aruba | 845398-B21 |
|---|---|
| Manufacturer | HT |
| HT Part Number | SFP-25GSR-85 |
| Form Factor | SFP28 |
| Max Data Rate | 25.78Gbps |
| Wavelength | 850nm |
| Max Cable Distance | 100m@OM4/70m@OM3 |
| Connector | Duplex LC |
| Media | MMF |
| Transmitter Type | VCSEL |
| Receiver Type | PIN |
| TX Power | -8.4~2.4dBm |
| Minimum Receiver Power | <-5.6dBm |
| Power Budget | 2.8dB |
| Receiver Overload | 2.4dBm |
| Power Consumption | ≤1W |
| Extinction Ratio | ＞2dB |
| CDR (Clock and Data Recovery) | TX & RX Built-in CDR |
| Inbuilt FEC | Yes |
| Commercial Temperature Range | 0 to 70°C (32 to 158°F) |
| Protocols | SFF-8472, SFF-8024, SFF-8431, SFF-8432 |
| DDM/DOM | Supported |
| Core Size | 50/125 µm |
| Packaging Technology | COB Packaging |
Field Installation and Maintenance
Inspect the connector and patch lead before installation, then support the fiber without pulling on the module housing. Release the latch properly during maintenance and keep dust protection on unused interfaces. If a module is removed for later use, retain its part-number label and record its original port. For this model, the principal parameters are data rate 25.78Gbps, wavelength 850nm, rated reach 100m on OM4 / 70m on OM3.
Applications and Optical Link Design
Typical deployments include switch-to-switch, switch-to-server and aggregation links inside a data hall or between adjacent equipment rooms. The Duplex LC interface connects to the specified multimode cabling, and the stated reach depends on fiber grade and link loss. Keep this interface on the matching multimode optical standard rather than connecting it directly to a single-mode wavelength or reach variant.
Before deployment, check the host port type, supported data rate and firmware requirements. The 25G interface configuration must match the remote equipment; sharing a SFP28 housing alone does not make two transceiver types interoperable.
For this multimode module, confirm fiber grade, modal bandwidth and total loss before commissioning. The 100m on OM4 / 70m on OM3 figure applies only under suitable cabling conditions. Inspect every Duplex LC mating point and match the remote optical standard.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -8.4~2.4dBm; the stated optical power budget is 2.8dB. A sound acceptance record includes link state, diagnostic temperature, supply voltage and transmit or receive levels where the host exposes them. Compare the readings with the stated ranges rather than treating any received light as proof of adequate margin. Persistent alarms or borderline values should trigger an end-face and complete-channel inspection. Diagnostic monitoring is listed as Supported. Before every insertion, keep dust caps in place until the patch lead is ready, avoid touching the optical end face and use an appropriate inspection and cleaning procedure. Do not look into an active optical interface.
Quality Assurance and Packaging
Quality control covers the optical or electrical interface, host identification and operating link. The verified unit is then individually protected and cartoned. Customer references, rack groups and project packing lists can be added for volume orders.
HPE Aruba Compatibility and Factory Testing
Compatibility testing for 845398-B21 combines identification with a live link and available transmit, receive and alarm information. Connector condition is inspected separately. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Frequently Asked Questions
Is this an original HPE Aruba transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies 845398-B21, not an original HPE Aruba-branded module.
Which fiber and connector are required?
Use Duplex LC with MMF. The specified maximum reach is 100m on OM4 / 70m on OM3, subject to fiber quality and total link loss.
Can it be mixed with another wavelength or reach version?
Only when the two ends share the same optical standard, wavelength plan and supported data rate. Check the exact part numbers and link budget rather than relying only on the module form factor.
Ordering Information
Quote HT part number SFP-25GSR-85 together with OEM reference 845398-B21 and quantity. Add the host model and software release when pre-order verification is required. Neutral labels, customer packaging and project-specific compatibility review are available on request.
Shipping and Lead Time
Standard configurations normally ship within one to three working days, with production lead times confirmed for larger quantities. International courier, air freight and sea freight are available; customer courier accounts and nominated forwarders are accepted.
