Cisco 100GBASE LR4 QSFP Transceiver, LC, 10km over SMF

Experience scalable, high-performance Ethernet connectivity with Cisco’s 100GBASE LR4 QSFP Transceiver. This compact, high-density optic is engineered for demanding data-center ecosystems, core and distribution layers in enterprise networks, and service-provider deployments that require stable 100 Gigabit Ethernet links. The LR4 specialization—leveraging four parallel 25 Gbps lanes over a single-mode fiber (SMF) link—delivers an elegant blend of long reach, precision optics, and seamless integration with Cisco’s trusted networking portfolio. Whether you are upgrading a hyperscale data center, bolstering inter-rack fabric, or enabling high-bandwidth links between data centers, this transceiver helps you achieve lower total cost of ownership through density, efficiency, and reliability.

• High-density 100GBASE LR4 optics — The transceiver uses a Quad Small Form-Factor Pluggable (QSFP+) package to deliver a total 100 Gbps of holistic bandwidth via four 25 Gbps lanes. This architecture minimizes port sprawl while maximizing data throughput for spine-leaf architectures and aggregation layers. It’s the ideal choice for operators seeking scalable uplinks between switches, routers, and data-center fabrics without sacrificing space or power budgets.
• Long-reach SMF with multiplexed wavelengths — Leveraging four independently modulated 25 Gbps channels at 1310 nm, LR4 technology enables precise wavelength-division multiplexing over a single-mode fiber path. The result is a robust 10 km reach, reducing the need for expensive fiber refreshes and enabling flexible geography for intersite connectivity, disaster recovery links, and campus-wide deployments. The optical design supports stable performance across varying fiber conditions, helping preserve signal integrity in dense data-center environments.
• LC duplex connector for broad compatibility — The LC duplex optical interface aligns with standard SMF cabling used across most data centers and enterprise networks. This familiar connector type simplifies installation, reduces the risk of mis-pairing fibers, and enables rapid cross-connects in patch panels and distribution frames. Its compatibility with Cisco gear and many third-party devices helps streamline procurement and maintenance workflows.
• Low power, hot-swappable design — Built for efficiency, the LR4 QSFP transceiver minimizes power draw while delivering uncompromised performance. As a hot-swappable module, it enables non-disruptive maintenance windows and easy field upgrades, supporting proactive capacity expansion and network modernization without forklift upgrades. The design also integrates thermal management features to sustain performance in dense 1U or 2U chassis configurations found in modern data centers.
• Cisco reliability with monitoring and compatibility — Cisco optics are engineered to integrate smoothly with Cisco routers, switches, and optical modules, offering dependable operation within Cisco’s software ecosystem. Many units support Digital Diagnostic Monitoring (DDM) for real-time health and status data, enabling proactive maintenance and quicker fault isolation. This reliability translates to higher uptime, consistent latency characteristics, and predictable performance for business-critical applications.

Technical Details of Cisco 100GBASE LR4 QSFP Transceiver, LC, 10km over SMF

• Form Factor: QSFP+ (Quad Small Form-Factor Pluggable)
• Data Rate: 100 Gbps aggregate across four 25 Gbps lanes (4x25 Gbps)
• Standard: 100GBASE-LR4 compliant, suitable for long-reach single-mode fiber links
• Wavelengths: Four 1310 nm channels per transceiver for DWDM-like LD multiplexing on SMF
• Reach: Up to 10 kilometers over standard single-mode fiber with appropriate fiber and connectors
• Connector: LC duplex optical connector
• Fiber Type: Single-Mode Fiber (SMF)
• Diagnostics: Digital Diagnostic Monitoring (DDM) capability for real-time optical performance data
• FEC Support: Forward-error correction support to enhance link reliability and frame integrity
• Compatibility: Designed to integrate with Cisco platforms and other compatible networking gear that supports 100GBASE-LR4 QSFP+ modules
• Operating Conditions: Commercial-range operating environment suitable for standard data-center climates

How to Install Cisco 100GBASE LR4 QSFP Transceiver, LC, 10km over SMF

Step 1: Prior to installation, inspect the transceiver and the QSFP+ port for any packaging residue or protective caps. Remove the protective caps carefully from both the transceiver and the fiber connectors only after verifying that the receiving hardware is powered down or in a maintenance window, to prevent electrostatic discharge or accidental damage.

Step 2: Align the LR4 QSFP+ module with the destination switch or router’s 100G QSFP+ port. Insert the module straight into the port until it seats securely with an audible click or tactile confirmation, indicating proper engagement. Do not apply sideways force; misalignment can damage either the transceiver or the host port.

Step 3: Connect the SMF fiber pair using the LC duplex connectors. Ensure both transmit and receive fibers are properly aligned and seated in the correct ferrules. Verify that the fiber type and length meet the link’s requirements for the 10 km reach. Avoid bending fibers beyond recommended radii and keep connections clean to minimize insertion loss.

Step 4: Power on the device and monitor link status via the network device’s management interface. Use the appropriate Cisco commands or GUI to verify that the 100G link is up and that the transceiver’s diagnostics are reporting nominal values. If available, enable FEC and confirm that corrected codewords are within expected tolerances for sustained throughput.

Step 5: Perform end-to-end testing to validate throughput, latency, and error rates across the link. Confirm that Digital Diagnostic Monitoring data reflects stable optical power levels, extinction ratios, and temperature ranges. Schedule a health-check routine in your network operations center to track aging indicators and plan proactive replacements as needed.

Step 6: Document the installation in your change-management records, including the part number, serial, firmware version, and cabling topology. Maintain an inventory of spare LR4 QSFP+ modules and ensure compatibility with existing hardware revisions to prevent incompatibilities during future upgrades.

Frequently Asked Questions

• What is the Cisco 100GBASE LR4 QSFP Transceiver? It is a high-density optical module designed for 100 Gigabit Ethernet using four 25 Gbps lanes in a QSFP+ form factor, with LC duplex connectors and an up-to-10 km reach on single-mode fiber. It supports long-haul links between data centers and within large enterprise networks, delivering scalable performance while conserving rack space.
• What kind of fiber and connectors does it use? The LR4 transceiver uses single-mode fiber (SMF) with an LC duplex connector. This configuration is widely adopted in data centers and carrier networks for long-distance links, and it is compatible with standard SMF cabling and patch panels.
• Is this module compatible with non-Cisco devices? Generally, LR4 QSFP+ modules that conform to 100GBASE-LR4 specifications can work in other vendors’ devices that support the same standard. However, some features (like certain management or diagnostic functions) may be vendor-specific. Always verify interoperability with your network hardware vendor before deployment.
• Does it support Digital Diagnostic Monitoring (DDM)? Yes, the module typically includes DDM capabilities, providing real-time measurements such as optical power, temperature, supply voltages, and transceiver status to assist with proactive maintenance and rapid fault isolation.
• What are common use cases for this transceiver? Common deployments include 100G uplinks in spine-leaf data-center fabrics, inter-switch or router connections in core networks, metro or campus backbones, and service-provider interconnects requiring scalable, long-reach 100G links with minimal fiber footprint.
• What maintenance or replacement considerations exist? Regular monitoring via DDM, prompt replacement of any transceiver showing abnormal power levels or temperature spikes, and adherence to proper handling to avoid ESD or micro-bend damage are recommended. Keep spare modules in anti-static packaging and within recommended storage conditions.
• What is the expected warranty or support? Cisco optics typically come with a hardware warranty and access to Cisco's technical support, firmware updates, and compatibility documentation. Check your purchase agreement for exact coverage terms and renewal options.