Cisco 40GBase-LR4L QSFP Module for SMFEngineered for performance, efficiency, and reliability, the Cisco WSP Q40GLR4L QSFP Module enables 40 Gigabit Ethernet connectivity over long haul single mode fiber. This LR4L transceiver is designed for dense data centers, cloud environments, and service provider backbones where scalable uplinks, low latency, and robust signal integrity matter. The device fits standard QSFP+ ports, providing a compact, hot swappable solution that minimizes rack