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by Cisco
Product Line: Cisco QSFP Series
Product Type: QSFP-40GE-LR4
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Original price $0.00 - Original price $466.00
Original price
$0.00 - $466.00
Current price $0.00
Title: Surplus

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Product Description

The QSFP-40GE-LR4 Cisco transceiver supports a 40 GbE data rate and operates on 4 wavelengths (1271 nm, 1291 nm, 1311 nm, 1331 nm) over a single-mode fiber (SMF) with a core size of G.652 microns. It features a duplex LC connector, designed for long-reach applications up to 10 km, and maintains a transmit power range between -7 dBm to 2.3 dBm per lane with a receive power spectrum of -13.7 dBm to 2.3 dBm per lane. The device operates within a commercial temperature range of 0 °C to 70 °C, ensuring reliable performance across varied environmental conditions.

Key Feature for the QSFP-40GE-LR4

  • What is the data rate supported by the 40GBASE-LR4 transceiver?
    The data rate supported is OTU3.
  • How many wavelengths are supported and what are they?
    The transceiver supports 4 wavelengths: 1271 nm, 1291 nm, 1311 nm, and 1331 nm.
  • What type of cable is required for the transceiver?
    SMF (Single-Mode Fiber) with a core size of G.652 microns is required.
  • What are the maximum and minimum operating temperatures of the 40GBASE-LR4?
    The operating temperature ranges from 0 °C (minimum) to 70 °C (maximum).
  • What type of connector is used with this transceiver?
    A Duplex LC connector is used.
  • Can you detail the power specifications for transmitting and receiving on the 40GBASE-LR4 transceiver?
    Maximum transmit power is 2.3 dBm per lane, minimum transmit power is -7 dBm per lane, maximum receive power is 2.3 dBm per lane, and minimum receive power is -13.7 dBm per lane.
  • What are the physical dimensions of the transceiver?
    The dimensions are 13.5 mm in height, 18.4 mm in width, and 72.4 mm in depth, with a weight of 100 g or less.
  • What laser class is the transceiver equipped with and what are its wavelength multiplexing capabilities?
    It is equipped with a Laser Class 1 and supports both wavelength multiplexing and demultiplexing.
  • What is the link reach and signal strength of the transceiver?
    The link reach is up to 10 km with a signal strength of 40 GbE.
  • What are the storage temperature limits of the transceiver?
    The storage temperature ranges from -40 °C (minimum) to 85 °C (maximum).

Product Review

The Cisco QSFP-40GE-LR4 transceiver offers a strong solution for long-reach data transmission needs, supporting distances up to 10 km over single-mode fiber with a data rate of 40 GbE, making it suitable for extended network deployments. However, its operational temperature range from 0°C to 70°C may limit its use in environments with extreme temperatures. Additionally, the transceiver's support for both wavelength multiplexing and demultiplexing across four wavelengths (1271 nm, 1291 nm, 1311 nm, 1331 nm) enhances its versatility in complex fiber optic networks.


The Cisco QSFP-40GE-LR4 is a high-performance 40-Gigabit Ethernet transceiver designed to meet the demands of high-density networking environments. It is compatible with the 40GBASE-LR4 specification, enabling long-range data transmission up to 10 kilometers over single-mode fiber (SMF). This transceiver is equipped with a duplex LC connector, making it suitable for a wide range of networking equipment. One of the key features of the QSFP-40GE-LR4 is its support for four wavelengths (1271 nm, 1291 nm, 1311 nm, 1331 nm), which allows for efficient data transmission and reception. This multi-wavelength support is facilitated by integrated wavelength multiplexing and demultiplexing capabilities, ensuring optimal performance and compatibility with existing network infrastructure. The transceiver operates within a commercial temperature range of 0 °C to 70 °C, ensuring reliability and stable performance under varying environmental conditions. Additionally, it is designed to withstand storage temperatures ranging from -40 °C to 85 °C, further attesting to its durability. In terms of optical power, the QSFP-40GE-LR4 features a maximum transmit power of 2.3 dBm per lane and a minimum transmit power of -7 dBm per lane. Similarly, it supports a maximum receive power of 2.3 dBm per lane and a minimum receive power of -13.7 dBm per lane. This range of power levels ensures compatibility with a variety of network configurations and distances. The transceiver has a compact form factor, with dimensions of 13.5 mm in height, 18.4 mm in width, and 72.4 mm in depth, and it weighs 100 grams or less. Its small size and light weight make it an ideal choice for installations where space is at a premium. The Cisco QSFP-40GE-LR4 is classified as a Class 1 laser product, adhering to strict safety standards to prevent optical harm. It utilizes a G.652 micron core size for the SMF, which is the standard core size for most single-mode fibers, ensuring broad compatibility. Key specifications include: -
  • Signal strength of 40 GbE, supporting high-speed data transmission.
  • Data rate support for OTU3, facilitating efficient optical transport network configurations.
  • Long reach type, suitable for extended network connections up to 10 kilometers.
In summary, the Cisco QSFP-40GE-LR4 transceiver offers a blend of performance, reliability, and compatibility for networking professionals seeking to upgrade or expand their 40 Gigabit Ethernet infrastructure. Its support for multiple wavelengths, along with integrated multiplexing and demultiplexing capabilities, makes it a versatile solution for a wide range of networking applications. Whether for data centers, enterprise networks, or service provider environments, the QSFP-40GE-LR4 is engineered to deliver long-distance, high-speed networking with uncompromised integrity and safety.


Item Number Cisco QSFP-40GE-LR4
Manufacturer Cisco
Form Factor 40GBASE-LR4 Transceiver
Highest Output Power Per Channel 2.3 dBm
Lowest Output Power Per Channel -7 dBm
Peak Receiving Power Per Channel 2.3 dBm
Minimum Receiving Power Per Channel -13.7 dBm
Channel Count 4
Operational Wavelengths 1271 nm, 1291 nm, 1311 nm, 1331 nm
Safety Laser Rating Class 1
Connection Interface Duplex LC
Fiber Type Single-Mode Fiber (SMF)
Fiber Core Diameter G.652 Microns
Operating Temperature Low End 0 °C
Operating Temperature High End 70 °C
Storage Temperature Low End -40 °C
Storage Temperature High End 85 °C
Network Speed Capability 40 GbE
Maximum Transmission Distance 10 km
Physical Height 13.5 mm
Physical Width 18.4 mm
Physical Depth 72.4 mm
Unit Weight 100 g Maximum
Supported Data Rate OTU3
Support for Wavelength Multiplexing Supported
Support for Wavelength Demultiplexing Supported
Distance Capability Long Range

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