| Network Technology | 100GBase-ER4 |
| Fiber Mode Supported | Single-mode |
| Media Type Supported | Optical Fiber |
| Ethernet Technology | 100 Gigabit Ethernet |
| Fiber Optic Cable Standard | G.652 µm |
| Depth | 2.85" (72.40 mm) |
| Width | 0.72" (18.40 mm) |
| Height | 0.53" (13.50 mm) |
| Brand Name | Cisco |
| Application/Usage | Optical Network |
| Product Name | 100GBASE QSFP Transceiver, 25-40KM Reach Over SMF, Duplex LC |
| Manufacturer | Cisco Systems, Inc |
| Weight (Approximate) | 3.53 |
| Interfaces/Ports Details | 1 x LC Duplex 100GBase-ER4 Network |
| Marketing Information | The Cisco QSFP100 ER4-Lite supports link lengths of up to 40km over a standard pair of G.652 single-mode fiber with duplex LC connectors. The 100 Gigabit Ethernet signal is carried over four wavelengths. Multiplexing and demultiplexing of the four wavelengths are managed within the device. Full 40km reach requires the use of FEC on the host platform. Without FEC, the reach is 30km. The QSFP100 ER4-Lite provides backward compatibility with Cisco's CPAK ER4-Lite, whose reach is up to 25km, and with IEEE 100GBASE-ER4 standardized transceivers, such as Cisco's CFP 100G ER4, up to 30km. It also interoperates with Cisco's QSFP100 and CPAK IEEE 100GBASE-LR4 modules up to 10km. |
| Manufacturer Website Address | http://www.cisco.com |
| Manufacturer Part Number | QSFP-100G-ER4L-S= |
| Product Type | QSFP |
Cisco QSFP-100G-ER4L-S 100GBASE QSFP Transceiver, 40KM LC, SMF

Key Benefits
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- Enables long-distance 100G Ethernet connectivity up to 40km, ideal for large-scale distributed networks
- Supports seamless integration into existing Cisco environments with backward compatibility to multiple transceiver platforms
- TAA compliance ensures eligibility for government contracts and regulated deployments
Product Overview
The Cisco QSFP-100G-ER4L-S transceiver is built for high-capacity 100G Ethernet applications requiring long-distance reach over single-mode fiber (SMF). With support for link lengths up to 40km when used with Forward Error Correction (FEC), this module enables efficient, scalable data center interconnects and carrier-grade networks. The device transports the 100G Ethernet signal using four wavelength channels on a standard duplex LC connector setup, with integrated multiplexing and demultiplexing for simplified integration and deployment.
Designed to support the G.652 µm fiber optic standard, the module ensures consistent signal integrity across long distances. It provides backward compatibility with Cisco’s CPAK ER4-Lite modules (25km) and IEEE 100GBASE-ER4 CFP Ethernet modules (30km), while also interoperating with IEEE 100GBASE-LR4 modules up to 10km, enhancing flexibility in multi-platform environments. With compact QSFP form factor dimensions (0.53" height x 0.72" width x 2.85" depth) and a weight of 3.53g, the transceiver offers robust performance in a space-efficient design, complying with TAA regulations for government procurement.
Specifications
Primary Information
UNSPSC Code
| UNSPSC Code | 43222608 |
Special Feature
| COO | CHINA / JAPAN |
| TAA compliance | Yes |
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