Extreme 40GB-ESR4-QSFP Compatible 40G QSFP+ ESR4 Transceiver Module

Built for hosts recognizing 40GB-ESR4-QSFP, this HT-manufactured QSFP+ module delivers 40G transmission at 850nm. Its rated reach is 400m on OM4, with MTP/MPO-12 Male as the physical interface. The specifications and engineering guidance below support structured fiber installations preserve a documented and serviceable optical channel, while keeping HT manufacture separate from the OEM cross-reference.
OEM Part Number: 40GB-ESR4-QSFPHT Part Number: QSFP-CSR4-40G
Product Highlights
- Compatible alternative to Extreme 40GB-ESR4-QSFP
- 40G connectivity at 42Gbps (4x 10.5Gbps)
- Optical wavelength: 850nm
- Specified reach: 400m on OM4
- MTP/MPO-12 Male / MMF interface
- Operating temperature: 0 to 70°C (32 to 158°F)
- Factory compatibility verification and optical performance testing before shipment
Specifications
| Extreme Networks Compatible | 40GB-ESR4-QSFP |
|---|---|
| Manufacturer | HT |
| HT Part Number | QSFP-CSR4-40G |
| Form Factor | QSFP+ |
| Max. Data Rate | 42Gbps (4x 10.5Gbps) |
| Wavelength | 850nm |
| Max. Transmission Distance | 400m@OM4 |
| Connector | MTP/MPO-12 Male |
| Media | MMF |
| Transimitter Type | VCSEL 850nm |
| Receiver Type | PIN |
| TX Power | -7.5~0dBm |
| Receiver Sensitivity | <-9.9dBm |
| Power Budget | 2.4dB |
| Receiver Overload | 2.4dBm |
| Max. Power Consumption | ≤1.5W |
| Extinction Ratio | >3dB |
| Host FEC | Supported |
| Bit Error Ratio (BER) | 1E-12 |
| Operating Temperature | 0 to 70°C (32 to 158°F) |
| Protocols | 40G Ethernet, SATA/SAS3, IEEE 802.3ba, MSA Compliant |
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 MTP/MPO-12 Male 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 40G interface configuration must match the remote equipment; sharing a QSFP+ housing alone does not make two transceiver types interoperable.
The multimode channel should use the fiber grade associated with the stated 400m on OM4 reach. Keep the MTP/MPO-12 Male end faces clean and avoid tight bends. Different multimode standards are not interchangeable merely because they share a connector.
Extreme Compatibility and Factory Testing
Factory verification starts with the expected 40GB-ESR4-QSFP 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.
Optical Acceptance, Diagnostics and Handling
For this model, the specified transmit-power range is -7.5~0dBm; receiver sensitivity is <-9.9dBm; the stated optical power budget is 2.4dB. During commissioning, record the host diagnostic readings after the link has stabilized and compare them with those limits. DOM values are useful operational indicators, but they do not replace calibrated optical measurements when a link is marginal. Investigate unexpected loss through connector inspection, cleaning and a channel measurement before replacing the module. 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.
Structured Fiber Pathways and Serviceability
Treat the transceiver as part of the complete channel. Follow the intended patch-panel route, maintain bend control and leave service access around the port. Confirm connector polish and fiber type at every mated pair; a documented service allowance is preferable to excess slack concealed inside a rack. For this model, the principal parameters are data rate 42Gbps (4x 10.5Gbps), wavelength 850nm, rated reach 400m on OM4.
Ordering Information
Quote HT part number QSFP-CSR4-40G together with OEM reference 40GB-ESR4-QSFP 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.
Quality Assurance and Packaging
Each 40GB-ESR4-QSFP compatible module is inspected, powered up and functionally checked before protective packing. Dust caps and individual trays shield the interface during transport. Customer references, rack groups and project packing lists can be added for volume orders.
Frequently Asked Questions
Is this an original Extreme transceiver?
No. It is an HT-manufactured compatible alternative for equipment that specifies 40GB-ESR4-QSFP, not an original Extreme-branded module.
Which fiber and connector are required?
Use MTP/MPO-12 Male with MMF. The specified maximum reach is 400m on OM4, 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.
10/100BASE-T SFP