Cisco SFP-25G-ER-S-I Compatible 25G SFP28 ER Transceiver Module

This Cisco SFP-25G-ER-S-I compatible transceiver provides 25G connectivity in a hot-swappable SFP28 package. Its optical design operates at 1310nm for up to 30km, using Duplex LC. Complete parameters and related OEM references help field technicians install, maintain and identify the exact compatible module.
OEM Part Number: SFP-25G-ER-S-IHT Part Number: SFP-25GERL-31-I
Product Highlights
- Compatible alternative to Cisco SFP-25G-ER-S-I
- 25G connectivity at 25.78Gbps
- Optical wavelength: 1310nm
- Specified reach: 30km
- Duplex LC / SMF interface
- Digital diagnostic monitoring: Supported
- Operating temperature: -40 to 85°C (-40 to 185°F)
Specifications
| Cisco Compatible | SFP-25G-ER-S-I |
|---|---|
| Manufacturer | HT |
| HT Part Number | SFP-25GERL-31-I |
| Form Factor | SFP28 |
| Max Data Rate | 25.78Gbps |
| Wavelength | 1310nm |
| Max Cable Distance | 30km |
| Connector | Duplex LC |
| Media | SMF |
| Transmitter Type | DML 1310nm |
| Receiver Type | APD |
| TX Power | -0.5~6.5dBm |
| Receiver Sensitivity | <-19.5dBm |
| Power Budget | 19dB |
| Receiver Overload | -4dBm |
| Power Consumption | ≤2W |
| Extinction Ratio | 4dB |
| DDM/DOM | Supported |
| Industrial Temperature Range | -40 to 85°C (-40 to 185°F) |
| CDR | TX & RX Built-in CDR |
| FEC Function | Not Support |
| Protocols | SFF-8472, SFF-8432, SFF-8431 |
| Core Size | G.652 |
| Packaging Technology | BOX 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 1310nm, rated reach 30km.
Applications and Optical Link Design
Use this module for equipment interconnection over the specified single-mode fiber plant, including enterprise backbone, campus, metro or data-center interconnect links according to its rated distance. Confirm that both ends use the same optical standard and wavelength plan, and allow for connector, splice and patch-panel loss within the stated power budget.
The industrial temperature rating makes this version appropriate for controlled outdoor cabinets, transport nodes and other installations exposed to wider ambient temperature variation. Adequate airflow, protected cable routing and host-platform temperature limits still apply.
The single-mode link budget should include fiber attenuation, connectors, splices and panels over the intended 30km route. Keep the Duplex LC interface clean and match the remote optical standard. Consider receiver overload as well as insufficient power on short links.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -0.5~6.5dBm; receiver sensitivity is <-19.5dBm; the stated optical power budget is 19dB. 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.
Cisco Compatibility and Factory Testing
Factory verification starts with the expected SFP-25G-ER-S-I identity and finishes with an operating host link. EEPROM data, diagnostic visibility and the stated optical parameters are assessed together. Equipment model, hardware revision and software release can be reviewed before dispatch where platform behavior is uncertain.
Frequently Asked Questions
Is this an original Cisco transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies SFP-25G-ER-S-I, not an original Cisco-branded module.
Which fiber and connector are required?
Use Duplex LC with SMF. The specified maximum reach is 30km, 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
Use SFP-25G-ER-S-I as the compatibility cross-reference and SFP-25GERL-31-I as the HT ordering identity. Keep other reaches or wavelength directions on separate order lines. 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.
