Cisco QSFP-40G-SR4 Compatible 40GBase-SR4 QSFP+ 850nm 150m DOM MPO MMF Optical Transceiver Module

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QSFP-40G-SR4-FL Cisco (40GBase-SR4) Optical Transceiver

Example Application

Platform Support

Full Line of 40GBase-SR4 Transceivers

Data Sheet: HTML PDF

FluxLight's QSFP-40G-SR4-FL is a Cisco® compatible 40GBase QSFP+ Optical Transceiver and is factory pre-programmed with all the necessary configuration data for seamless network integration. This Cisco 40GBase-SR4 performs identically to Cisco® original transceivers and is 100% compatible with other OEM and third party transceivers. The Cisco QSFP-40G-SR4-FL is 100% MSA (Multi-Source Agreement) compliant. All FluxLight's transceivers are tested for 100% functionality and guaranteed compatible for outstanding network performance.

FluxLight offers all brands and form factors of Optical Transceivers for all your networking needs. Now you have a reliable, compatible and affordable means to expand your network while maintaining its integrity.


Example Application for Cisco QSFP-40G-SR4-FL (40GBase-SR4) Optical Transceiver

BUILD IT BETTER: Connecting Cisco Nexus 9336C-FX2 40G QSFP+ ports to HPE ProLiant DL360 Gen10 Rack Servers

Cisco 9336C-FX to Dell R640 |

Example 2: Connecting Cisco Nexus 9336C-FX2 40G QSFP+ ports to HPE ProLiant DL360 Gen10 Rack Servers Equipped with HPE 530SFP+ 10GbE 2-port Network Adapters.

Continuing in our series on options for the connection of a leaf switch to rack-mounted servers, we are going to step up the complexity to achieve higher connectivity density. In our previous post (see: FluxLIght Blog) connecting the leaf switch to the servers were simple 10Gbps SFP+-to-SFP+ (point to point) links using OM3 multimode fiber. In today’s post we will use 40Gbps QSFP+ ports on the leaf switch end of the connection. A point-to-multipoint connection will be used to allow each QSFP+ port to connect to four separate SFP+ ports on the servers.

In the previous post, four SFP+ ports in the Nexus 93180YC-FX switch supported connections to two servers, each connected using two 10Gbps links. By using the 40Gbps ports on the Nexus 9336C, a single QSFP+ slot supports two servers…a 4:1 reduction in the number of switch ports.

TOR Leaf Switch: Cisco Nexus 9336C-FX2

 Cisco Nexus 9336C-FX2 TOR Leaf Switch |

The Nexus® 9300-FX platform is part of the latest generation of the fixed Nexus® 9000 Series Switches. Cisco has coined the phrase “Cisco Cloud Scale (CCS)” to describe the technology on which this series is based. The primary elements of CCS are,

  • Greater performance scaling using multi-rate ports (1/10/25/50/100G)
  • Lower Total Cost of Ownership
  • Real-time telemetry and analytics with greater detail
  • Improved security through line-rate encryption
  • Faster application completion time

The Cisco Nexus 9336C-FX2 Switch is a 1RU switch that supports 7.2 Tbps of bandwidth and over 2.8 bpps (billion packets per second). This particular model is easily the most flexible of the Nexus 9300 line. Each of the switch’s 36 ports can be configured to work as 1/10/25/40/100-Gbps. The ports natively support QSFP+ (40Gbps) and QSFP28 (100Gbps) modules. 1G (SFP), 10G (SFP+) and 25G (SFP28) are supported using adaptors called QSAs. All ports support full line rate encryption (MACsec). Breakout, 40G to 4x10G and 100G to 4x25G, is supported on all ports.

Rack-mounted Server: HPE ProLiant DL360 Gen10 Server

 HP ProLiant DL360 Gen10 Server |

HPE claims, “The powerful 2P HPE ProLiant DL360 Gen10 is redefining dense compute by delivering security, agility and unmatched expandability businesses want all packed in a dense 1U rack design.” The ProLiant DL360 Gen10 Server is based Intel® Xeon® processor(s) and can be ordered with up to 28 cores, plus HPE DDR4 SmartMemory operating at 2.666 Billion Transfers/Second (GT/s) supporting up to 3.0 TB maximum memory space. To further boost performance, the Non-Volatile Memory of the HPE ProLiant DL360 Gen10 includes 12 NVDIMMs and 10 NVMe (SSD). This platform “supports diverse workloads in space constrained environments and maintains it with ease by automating the most essential server lifecycle management tasks with HPE OneView and HPE iLO 5.”

Dual-SFP+ Port 10G Adaptor: HPE 530SFP+ Network Adaptor

 HP 530SFP+ Network Adaptor |

The HPE is an Ethernet adapter with 2 SFP+ 10Gbps ports in a PCIe 2.0 compliant form factor. It is compatible with select HPE ProLiant Gen10, Gen9, Gen8 and Gen7 ML/DL/SL servers. The HPE 530SFP+ combines full line-rate performance across both ports with low power consumption (less than 8 watts max). Ethernet transfer rate of 20 Gbps full duplex per port (40 Gbps aggregate) improves response times and alleviates bottlenecks in next generation data centers. The adaptor supports enterprise class features such as VLAN tagging, adaptive interrupt coalescing, MSI-X, NIC teaming (bonding), Receive Side Scaling (RSS), jumbo frames, PXE boot and virtualization features such as VMware NetQueue and Microsoft VMQ.

10GBASE-SR Optical Transceivers: FluxLight QSFP-40G-SR4-FL and FluxLight J9150A

qsfp-40g-sr.jpgHP J9150A Compatible 40GBase-SR4 QSFP+ 850nm Optical Transceiver Module |

FluxLight's QSFP-40G-SR4-FL is a Cisco® compatible 40GBase-SR4 SFP+ Optical Transceiver and is factory pre-programmed with all the necessary configuration data for seamless network integration. It supports 4 lanes of 10Gbps Ethernet transmission over up to 150 meters of OM3 multimode fiber and transmits at 850nm. The four 10Gbps lanes each travel over 2 fibers in an MPO-12 cable (4 unused fibers). These transceivers perform identically to Cisco® original transceivers and are 100% compatible and support full hot swappable operation. The QSFP-40G-SR4-FL is 100% MSA (Multi-Source Agreement) compliant, see: QSFP+ MSA, SFF-8436.

FluxLight's J9150A is fully compliant with the SFP+ MSA (SFF-8431) and backed by Fluxlight’s limited lifetime warranty. The primary difference between the SFP-10G-SR (highlighted in our previous post) and the J9150A is compatibility. The J9150 is an HPE® compatible 10GBase-SR SFP+ optical transceiver. It is pre-programmed by Fluxlight with all the necessary configuration data for seamless integration into all supporting HPE equipment. These transceivers perform identically to HPE® original transceivers and support hot swappable operation.

Jumper Cables: MPO to 4 x Dual LC OM3 Multimode Breakout Cable

 MPO to 4xDual-LC OM3 |

To connect the QSFP+ ports in the Cisco Nexus 9336C-FX2 to the 530SFP+ network adaptor modules in in the ProLiant DL360, an MPO to 4x Dual-LC breakout cable is used. The MPO end of the cable is inserted into the Fluxlight QSFP-40G-SR4-FL. Each of the Dual-LC connectors are inserted into one the Fluxlight J9150A SFP+ modules which are installed in the HPE 530SFP+ network adaptors installed in the ProLiant DL360 servers. 

Putting it all together

We’ve listed all the components so now we need to connect the bits together. The Cisco Nexus 9336C-FX2 switch only uses 1RU and is customarily placed at the top of the rack. Each HPE ProLiant DL360 server also uses only 1RU. Since we are running two 10Gbps links per server, two Fluxlight 10GBASE-SR modules must be installed in each of the network adaptor cards (530SFP+). In this case the optical transceivers must HPE compatible, so the correct Fluxlight part number is J9150A.

The Nexus 9336C-FX2 switch contains 36 multi-rate slots. Assuming not all of the traffic is locally connecting between the local ProLiant servers, we will set aside enough ports that, when equipped with 100G QSFP28 modules (for example, FluxLight QSFP-100G-SR4) will support approximately all the traffic to/from the subtending servers (downlinks).  If we allocate 26 ports to 40G QSFP+ connections to servers, that is a total of 1.04 Terabits/sec (Tbps) downlink capacity. Equipping the remaining 10 ports with 100G QSFP28 optical transceivers, brings the total uplink capacity to 10 x 100 or 1.0 Tbps, so just about a perfect split. Of course this is a bit simplistic. The actual allocation may involve many other factors including things like how many spine switches are used in the center design, predictions of intra-rack traffic, etc.

Finally, the MPO to 4x Dual-LC OM3 duplex multimode fiber jumper mentioned above, is used to connect to each QSFP+ module in the Nexus leaf switch to four SFP+ modules in the server NICs. Each QSFP+ module supports two servers with a total of 20Gbps (full-duplex) each. Since we have allocated 26 Nexus 9336C ports to 40G QSFP+ modules, that brings the total number of servers per 9336C switch to 52. In our previous post, using the 48 SFP+ 10Gbps ports on the Cisco Nexus 93180YC-FX, allowed only 24 subtended servers, so we have more than doubled the leaf-server density by using the 9336C-FX2 QSFP+ ports.

 Connecting Cisco Nexus 9336C-FX2 40G QSFP+ ports to HPE ProLiant DL360 Gen10 Rack Servers Equipped with HPE 530SFP+ 10GbE 2-port Network Adapters. |

Cisco QSFP-40G-SR4-FL Platform Support

Cisco QSFP-40G-SR4-FL is supported on a wide range of Cisco equipment.

Cisco Nexus 6000 N6K-C6001-64P Cisco Nexus 2000 N2K- 2332TQ Cisco Nexus 9000 N9K-C9372PX-E
Cisco ASR 9000 A9K-MPA-1X40GE Cisco Nexus 9000 N9K-M6PQ-E Cisco 3850 WS-C3850-48XS-S
Cisco Nexus 2000 N2K-C2248PQ Cisco Nexus 9000 N9K-M6PQ-E Cisco Nexus 9000 N9K-C9272Q
Cisco Nexus 9000 N9K-C9372PX Cisco Nexus 9000 N9K-M6PQ-E Cisco CRS 2x100GE-FLEX-40
Cisco Nexus 3000 N3K-C3164Q Cisco Nexus 9000 N9K-C92160YC-X Cisco C6800-SUP6T-XL
Cisco Nexus 3000 N3K-C31128PQ-10GE Cisco Nexus 9000 N9K-C9372PX Cisco Nexus 2000 N2K-2348UPQ
Cisco Nexus 9000 N9K-C9372TX-E Cisco Nexus 9000 N9K-X9464TX Cisco Nexus 9000 N9K-X9536PQ
Cisco Nexus 6000 N6004-B-24Q Cisco Nexus 9000 N9K-C9372TX-E Cisco Nexus 9000 N9K-C9336PQ
Cisco Nexus 9000 N9K-X9736PQ Cisco Nexus 9000 N9K-X9432PQ Cisco Nexus 6000 N6K-C6004-M12Q
Cisco Nexus 3000 N3K-3132Q Cisco Nexus 3000 N3K-C3064X Cisco Nexus 7000 N7K-M206FQ-23L
Cisco C3850-NM-2-40G Cisco Nexus 5000 N5K-C5672UP Cisco Nexus 9000 N9K-X9564PX (uplinks)
Cisco Nexus 9000 N9K-C9372TX-E Cisco Nexus 9000 N9K-C93120TX Cisco Nexus 5000 N5K-C56128P
Cisco Nexus 9000 N9K-M12PQ Cisco 6000 NCS-F-SCSW Cisco Nexus 6000 N6K-C6001-64T
Cisco 6800 C6824-X-LE-40G Cisco 3850WS-C3850-48XS-E Cisco Nexus 9000 N9K-C9372TX
Cisco Nexus 9000 N9K-C9332PQ Cisco Nexus 3000 N3K-C3016Q Cisco Nexus 5000 N55-M4Q
Cisco WS-C3850-48XS-F-S Cisco A9K-MPA-2X40GE Cisco Nexus 9000 N9K-C9372PX-E
Cisco Nexus 3000 N3K-3172PQ Cisco Nexus 3000 N3K-C3264Q Cisco Nexus 9000 N9K-M12PQ
Cisco Nexus 3000 N3K-C3064PQ-10GE Cisco Nexus 9000 N9K-M6PQ Cisco 6800 C6840-X-LE-40G
Cisco Nexus 7000 N7K-F312FQ-25 Cisco Nexus 2000 N2K- 2332TQ Cisco Nexus 9000 N9K-X9636PQ
Cisco Nexus 9000 N9K-X9464PX Cisco Nexus 9000 N9K-C9332PQ Cisco Nexus 3000 N3K-3172TQ
Cisco Nexus 9000 N9K-C93120TX Cisco Nexus 3000 N3K-C3232C Cisco Nexus 9000 N9K-M6PQ
Cisco Nexus 9000 N9K-X9564TX (uplinks) Cisco Nexus 6000 N6004-96Q Cisco Nexus 2000 N2K-2348TQ
Cisco Nexus 7000 N77-F324FQ-25 Cisco Nexus 3000 N3K-C3132Q-X Cisco Nexus 3000 N3K-C3064PQ
Cisco Nexus 9000 N9K-X9432C-S Cisco C6800-SUP6T  
Cisco Nexus 5000 N5K-C5672UP Cisco 6500 C6800-SUP6T  


All FluxLight QSFP+ 40GBase-SR4 Optical Transceivers

Alcatel-Lucent QSFP-40G-SR-FL
Alcatel-Lucent QSFP-40G-SR-FLT
Allied Telesis AT-QSFPSR4-FL
Arista QSFP-40G-SR4-A-FL
Arista QSFP-40G-SR4-A-FLT
Brocade-Foundry 40G-QSFP-SR4-FL
Chelsio SM40G-SR-FL
Cisco FET-40G-FL
Cisco QSFP-40G-SR4-FL
Cisco QSFP-40G-SR4-FLT
Cisco QSFP-40G-SR4-S-FL
Cisco QSFP-40G-SR4-S-FLT
Dell 407-BBOI-FL
Dell 407-BBOZ-FL
Dell 407-BBYS-FL
Dell 407-BBZU-FL
Enterasys 40GB-SR4-QSFP-FL
Extreme 10319-FL
F5  OPT-0025-00-FL
Finisar FTL410QD2C-FL
Finisar FTL410QD3C-FL
Finisar FTL410QD4C-FL
Finisar FTL410QE2C-FL
Finisar FTL410QE2N-FL
Finisar FTL410QE3C-FL
Finisar FTL410QE4C-FL
IBM 00D9865-FL
IBM 49Y7884-FL
Juniper QFX-QSFP-40G-SR4-FL
Juniper QFX-QSFP-40G-SR4-FLT
Juniper QSFPP-4X10GE-SR-FL
Juniper SRX-QSFP-40G-SR4-FL
Juniper SRX-QSFP-40G-SR4-FLT
Meraki MA-QSFP-40G-SR4-FL
Meraki MA-QSFP-40G-SR4-FLT
Nokia 3HE07928AA-FL
Nortel AA1404005-E6-FL

Product Quality

Since its inception in 2004, Fluxlight has continually refined its processes to assure the best possible quality for our customers. The foundational elements of these processes are Record-Keeping and Quality Assurance Testing (QAT). To maintain a robust data archive, each part is individually serialized both in its internal EEPROM memory and on its external label. All QAT results and other important information (e.g., manufacture date, compatibility programming) are associated with each Serial Number stored in our cloud-based secure database. QAT consists of visual part inspection as well as verification of all critical parameters and performance of each part. For the QSFP-40G-SR4 (Arista)-A-FLT optical output power and wavelength (850nm) are verified on optical spectrum analyzers. Receiver sensitivity is verified at both minimum distance and the 150m maximum range over actual (not simulated) MMF , multimode fiber cable. Digital Diagnostics Monitoring (DDM) parameters including: optical output power, receive optical power, internal module temperature, transmit bias current and supply voltage, are tested for compliance with specifications.In addition, the part is verified for proper operation across its full operating temperature range, 0C to 50C.


The following is a list of Finisar Corporation patents Fluxlight has licensed. This licensure recognizes and compensates Finisar for their intellectual property. The QSFP-40G-SR4-FL, like all Fluxlight optical transceivers, is covered by this license agreement. Therefore, Fluxlight customers can rest assured that all products purchased are fully licensed, and our customers are under no potential liability that may ensue from the use of unlicensed optical transceiver products.

U.S. Patent Numbers: 7,184,668 (System and method of protecting eye safety during operation of a fiber optic transceiver), 7,079,775 (Integrated memory mapped controller circuit for fiber optics transceiver), 6,957,021 (Optical transceiver with memory mapped locations), 7,058,310 (System and method for protecting eye safety during operation of a fiber optic transceiver), 6,952,531 (System and method for protecting eye safety during operation of a fiber optic transceiver), 7,162,160 (System and method for protecting eye safety during operation of a fiber optic transceiver), 7,050,720 (Integrated memory mapped controller circuit for fiber optics transceiver)

Original Equipment Manufacturer (OEM) names may be registered trademarks of the respective OEM, and the OEM has neither authorized nor sponsored the use of its trademark or trade name. All OEM names are used for cross reference/comparative purposes only.

Limited Lifetime Warranty

Fluxlight provides a non-transferable serviceable lifetime warranty to the purchaser of Fluxlight hardware product purchased from Fluxlight or an authorized Fluxlight reseller. Fluxlight warrants to the original end customer of its products specified below that its products are free from defects in material and workmanship affecting form, fit, and function. All such products sold will work in the application specified at the time of purchase and will meet the datasheet specifications as found on Fluxlight’s Web site or otherwise provided by Fluxlight. Any claim alleging that any product fails to conform to the foregoing may be made only by the customer who purchased such product and only while such customer owns such product and while the product remains within the serviceable lifetime period. Fluxlight, at its option, will repair, replace, or provide a credit or refund of either the original purchase price or fair market value, whichever is lower, of any product that is determined by Fluxlight to be defective. Some systems that use Fluxlight products may be allowed to operate outside of the system manufacturer’s published settings and Fluxlight does not cover failure in these circumstances. This warranty covers only defects arising under normal use and do not include malfunctions or failures resulting from misuse, abuse, neglect, alteration, problems with electrical power, usage not in accordance with product instructions, acts of nature, or improper installation or improper operation or repairs made by anyone other than Fluxlight or an Fluxlight authorized third-party service provider. Fluxlight reserves the right to substitute functionally equivalent new or serviceable used parts.

Form more information please see our warranty page.