QSFP-40G-SR4-S – 40G SR4 S-Class QSFP – MPO-12 MMF – No Breakout
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QSFP-40G-SR4-S Description
QSFP-40G-SR4-S is Cisco's S-Class 40GBASE-SR4 QSFP optical transceiver for native 40 Gigabit Ethernet links over laser-optimized multimode fiber. It uses an MPO-12 parallel fiber interface with four 10G optical lanes, supports up to 100 m on OM3 or 150 m on OM4/OM5, consumes 1.5W, and is specified for 0 to 70 degrees C operation. Cisco positions this -S optic for native 40G SR4 connections only, so it should be matched to a supported Cisco QSFP 40G host port rather than 4x10G breakout or FCoE designs.
Quick Specs
|
Parameter |
Specification |
|---|---|
|
Product ID |
QSFP-40G-SR4-S |
|
Product type |
40GBASE-SR4 S-Class QSFP optical transceiver |
|
Ethernet rate |
40 Gigabit Ethernet |
|
Connector type |
MPO-12 |
|
Fiber type |
Multimode fiber |
|
Optical lane design |
Four 10G optical lanes |
|
Wavelength range |
840 to 860 nm |
|
Reach on OM3 |
100m |
|
Reach on OM4 or OM5 |
150m |
|
Breakout support |
4x10G breakout not supported |
|
Power consumption |
1.5W |
Application Scenarios
QSFP-40G-SR4-S fits Cisco QSFP 40G ports where the installed fiber path is a 12-fiber MPO or MTP multimode run and the link remains a single 40GBASE-SR4 Ethernet connection.
Use this SKU in spares planning when the site standard allows S-Class SR4 optics and no connected design depends on four independent 10GBASE-SR endpoints from one QSFP port.
The optic should be matched against Cisco device-support documentation before quoting because a valid SR4-S module still needs support from the target switch, router, line card, QSFP port, and software release.
Product Comparison
|
Parameter |
QSFP-40G-SR4-S | |||
|---|---|---|---|---|
|
Product type |
40GBASE-SR4 S-Class QSFP transceiver |
40GBASE-SR4 QSFP transceiver |
40GBASE-CSR4 QSFP transceiver |
40GBASE-SR-BiDi QSFP transceiver |
|
Connector type |
MPO-12 |
MPO-12 |
MPO-12 |
Duplex LC |
|
Fiber type |
Multimode fiber |
Multimode fiber |
Multimode fiber |
Multimode fiber |
|
Optical lane design |
Four 10G lanes |
Four 10G lanes |
Four 10G lanes |
Two 20G BiDi channels |
|
Wavelength profile |
840 to 860 nm |
840 to 860 nm |
840 to 860 nm |
832 to 918 nm |
|
Reach on OM3 |
100m |
100m |
300m |
100m |
|
Reach on OM4 or OM5 |
150m |
150m |
400m |
150m |
|
4x10G breakout support |
Not supported |
Supported with external parallel-to-duplex breakout cable |
Supported with parallel-to-duplex breakout cable |
Not an SR4 breakout optic |
|
Power consumption |
1.5W |
1.5W |
1.5W |
3.5W |
|
Pull tab color |
Beige |
Beige |
Beige |
Gray |
- In a QSFP-40G-SR4-S vs QSFP-40G-SR4 comparison, the practical difference is breakout behavior: the S-Class part is documented for native 40G SR4 links only, while QSFP-40G-SR4 supports 4x10G breakout with the proper external fiber assembly.
- The QSFP-40G-SR4-S difference from QSFP-40G-CSR4 is reach and breakout scope; CSR4 keeps the MPO parallel interface but extends to 300m on OM3 and 400m on OM4 or OM5.
- QSFP-40G-SR4-S vs QSFP-40G-SR-BD is a connector comparison, because SR4-S uses 12-fiber MPO or MTP cabling while SR-BD uses duplex LC multimode fiber.
- For which model to choose, align the order with the required connector, multimode distance, breakout requirement, and Cisco host compatibility reference.
Selection Guide
1. Select it for native SR4 S-Class links
Choose QSFP-40G-SR4-S when the deployment needs a Cisco S-Class 40GBASE-SR4 QSFP module for a native 40G Ethernet link on MPO or MTP multimode fiber.
2. Avoid it for 4x10G breakout bills of materials
Use QSFP-40G-SR4 or QSFP-40G-CSR4 instead when the design requires one QSFP 40G port to connect to four 10GBASE-SR interfaces through breakout cabling.
3. Check the laser-optimized fiber class
Approve this SKU only when the planned run stays within 100m on OM3 or 150m on OM4 or OM5 fiber as documented for the S-Class SR4 optic.
4. Validate host support before release
Confirm the Cisco platform, module, QSFP 40G port, and software release in Cisco compatibility documentation before finalizing the quote.
Ordering Checklist
|
Check Item |
Required Evidence |
Error Avoided |
|---|---|---|
|
Native 40G use case |
The link is a single 40GBASE-SR4 Ethernet channel |
Prevents use of this SKU where the design needs 4x10G fan-out |
|
Cisco support matrix |
Platform, module, QSFP 40G port, and software release list SR4-S support |
Avoids installing a valid optic in an unsupported Cisco host |
|
MPO or MTP fiber plant |
12-fiber multimode trunk, polarity, and patch-panel path are documented |
Prevents LC BiDi or copper cable assumptions from entering the order |
|
Fiber distance class |
OM3 is within 100m, or OM4 or OM5 is within 150m |
Avoids over-reach and wrong fiber-grade planning |
|
Thermal and module power |
Host environment supports 0 to 70 degrees C operation and 1.5W module power |
Keeps chassis power and thermal checks tied to Cisco values |
|
FCoE requirement |
The planned link does not require FCoE support |
Avoids applying SR4-S to a protocol requirement Cisco excludes |
Specifications
| Parameter | Specification | Parameter | Specification |
|---|---|---|---|
| Product ID | QSFP-40G-SR4-S | Product type | 40GBASE-SR4 S-Class QSFP optical transceiver |
| Ordering description | Cisco 40GBASE-SR4 QSFP Module for MMF | Form factor | QSFP |
| Host interface | Cisco QSFP 40G port | Ethernet rate | 40 Gigabit Ethernet |
| Connector type | MPO-12 | Fiber type | Multimode fiber |
| Fiber core size | 50 microns | Modal bandwidth | 2000 MHz*km on OM3; 4700 MHz*km on OM4 or OM5 |
| Reach on OM3 | 100m | Reach on OM4 | 150m |
| Reach on OM5 | 150m | Breakout support | 4x10G breakout not supported |
| FCoE support | Not supported by QSFP-40G-SR4-S | Optical lane design | Four 10G lanes |
| Transmit and receive wavelength range | 840 to 860 nm | Transmit power per lane | -7.6 to +2.4 dBm |
| Receive power per lane | -9.5 to +2.4 dBm | Power consumption | 1.5W |
| Pull tab color | Beige | Operating temperature range | 0 to 70 degrees C |
| Storage temperature range | -40 to 85 degrees C | QSFP module dimensions | 13.5 x 18.4 x 72.4 mm maximum outer dimensions |
| QSFP module weight | 100 grams or less | IEEE relationship | Aligned to IEEE 40GBASE-SR4 optical specifications |
| Compatibility reference | Cisco Optics-to-Device Compatibility Matrix |
Get More Information
Need pricing, stock, or shipping details for the QSFP-40G-SR4-S ? Layer23-Switch can help you check current availability, lead time, and delivery options for this. Send us the part number, quantity, and destination country via live chat or email sales@layer23-switch.com for a fast quotation.
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Customer Reviews
Questions & Answers
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What connector does QSFP-40G-SR4-S use?
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What reach applies to QSFP-40G-SR4-S on MPO trunks?
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Can QSFP-40G-SR4-S break out into four 10G links?
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Why do buyers confuse QSFP-40G-SR4-S with QSFP-40G-SR4?
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Can QSFP-40G-SR4-S use existing LC duplex fiber?
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Is FCoE available on QSFP-40G-SR4-S?
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What platform check matters for QSFP-40G-SR4-S?
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Which deployment pattern fits QSFP-40G-SR4-S?
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