StarTech.com Arista QSFP-40G-LR4 Compatible QSFP+ Module — 40GBASE-LR4 SMF Transceiver

Experience high-performance 40 Gigabit Ethernet connectivity with StarTech.com's Arista QSFP-40G-LR4 compatible QSFP+ module. Engineered to match Arista Networks' rigorous requirements, this transceiver delivers dependable, low-latency LR4 operation over single-mode fiber while staying cost-effective and easy to deploy in data centers, campuses, and enterprise networks. With Digital Diagnostics Monitoring (DDM) support, you gain real-time visibility into optical power, temperature, and laser bias, helping you optimize link reliability and uptime. Whether you're upgrading an existing Arista-based fabric or building a new 40G spine-leaf topology, this module offers a seamless plug-in upgrade path that preserves throughput, reduces downtime, and simplifies inventory management. The module is designed to integrate smoothly with existing QSFP+ ports, delivering consistent performance across demanding multi-hop topologies and providing a scalable foundation for future network growth.

• 40GBASE-LR4 QSFP+ transceiver for high-density 40 Gigabit Ethernet connectivity over single-mode fiber (SMF), delivering full-duplex 40 Gbps data rates across long-reach LR4 links while preserving strict 40GBASE-LR4 standards compliance and interoperability with Arista networks.
• Arista-validated compatibility ensures reliable operation with Arista switches and routers, including seamless link negotiation, correct optical power budgets, and stable performance across a wide range of network topologies and workloads.
• Extended reach up to 10 kilometers on SMF, enabling efficient data center interconnects and campus deployments, with a 1310 nm optical wavelength and robust receiver sensitivity designed to maintain signal integrity on long-haul LR4 links.
• Digital Diagnostics Monitoring (DDM) support provides real-time insight into critical optical parameters (such as temperature, supply voltage, bias current, and optical power), empowering proactive maintenance, faster fault isolation, and easier capacity planning.
• Simple, hot-swappable QSFP+ form factor that plugs into standard 40G-capable switch/router ports with minimal downtime, reducing operational complexity and aligning with scalable, future-ready data center architectures.

Technical Details of StarTech.com Arista QSFP-40G-LR4 Compatible QSFP+ Module

• Form Factor: QSFP+
• Data Rate: 40 Gbps
• Wavelength: 1310 nm
• Fiber Type: Single-Mode Fiber (SMF)
• Reach: Up to 10 km
• Standards: 40GBASE-LR4
• Diagnostics: Digital Diagnostics Monitoring (DDM)
• Compatibility: Arista Networks switches and routers
• Interface: QSFP+ transceiver module

How to install StarTech.com Arista QSFP-40G-LR4 Compatible QSFP+ Module

• Power down the affected switch or router (or place the device into maintenance mode if required by your organizational procedures) before inserting the transceiver.
• Locate an available QSFP+ port that supports 40G Ethernet and carefully insert the module into the port until it seats securely with a click, ensuring proper orientation and alignment with the port cage.
• Connect the single-mode fiber cable to the transceiver using the appropriate LR4-compatible fiber link, ensuring the fiber is rated for 1310 nm operation and that the fiber polarity is correctly matched to the remote device.
• Power on the device and verify the link status through the switch/router management interface or CLI, confirming that the 40G interface comes up correctly and that the optical link is stable.
• Use the module’s Digital Diagnostics Monitoring (DDM) and compatible management tools to monitor optical power, temperature, and other parameters, adjusting configurations as needed to maintain optimal performance and reliability.

Frequently asked questions

• Is this compatible with Arista switches? Yes — the module is designed, programmed and tested to work with Arista Networks brand switches and routers.
• What is the maximum reach? Up to 10 kilometers on single-mode fiber (SMF) using the LR4 specification.
• Does it support Digital Diagnostics Monitoring (DDM)? Yes — the module includes DDM for real-time monitoring of optical and module parameters.
• What data rate does it support? 40 Gbps (40GBASE-LR4) on QSFP+ ports for full-duplex operation.
• What type of fiber and connectors are required? It uses single-mode fiber suitable for LR4 links; connectors follow LR4 standards and require appropriate fiber harnessing or direct-connect as supported by the host system.