StarTech.com Cisco QSFP-40G-CSR4 Compatible QSFP+ Module — 40GBASE-SR4 MMF Transceiver

The StarTech.com Cisco QSFP-40G-CSR4 Compatible QSFP+ Module is a high-performance optical transceiver designed to deliver reliable 40 Gigabit Ethernet connectivity over multimode fiber. Built to be Cisco CSR4 compatible, this QSFP+ transceiver provides a scalable, cost-efficient solution for data centers, enterprises, and service providers seeking to upgrade their network backbone without compromising interoperability. Engineered to work with Arista Networks switches and routers, it offers broader compatibility across major platform families, enabling seamless cross-vendor deployments and simpler network modernization. With stringent testing and quality assurance, this 40GBASE-SR4 MMF transceiver ensures stable operation in uplinks, spine-leaf architectures, and edge aggregation, while delivering solid performance for latency-sensitive applications such as storage, virtualization, and cloud services. Whether you’re consolidating racks, expanding high-density uplinks, or refreshing aging fiber optics, this transceiver is designed to integrate smoothly into your existing QSFP+ ports and fiber infrastructure.

• 40GBASE-SR4 over MMF: Supports 40 Gbps throughput using four independent 10 Gbps lanes, enabling high-density uplinks over multimode fiber for data centers and enterprise networks.
• Cisco CSR4 compatibility with broad interoperability: Specifically engineered to match Cisco CSR4 specifications while delivering reliable compatibility with Arista switches/routers and other major brands, reducing vendor lock-in and easing upgrades.
• Multimode fiber, 850 nm wavelength: VCSEL-based transceiver designed for MMF (OM3/OM4) fiber with an 850 nm wavelength, optimized for desktop-to-core distances in typical data center layouts.
• Plug-and-play, hot-swappable: Designed for straightforward installation in QSFP+ ports on compatible switches and routers, minimizing downtime and easing field deployments.
• Rigorous testing and reliability: The module is programmed, tested, and validated to work with Cisco CSR4 networks and Arista gear, delivering dependable performance in challenging environments.

Technical Details of StarTech.com Cisco QSFP-40G-CSR4 Compatible QSFP+ Module

• Product Type: QSFP+ transceiver module (40GbE) compatible with Cisco CSR4 specifications.
• Standard: 40GBASE-SR4 for multimode fiber networks.
• Data Rate: 40 Gbps aggregated bandwidth across four 10 Gbps lanes.
• Fiber Type: Multimode fiber (MMF) optimized for short- to medium-range links within data centers.
• Wavelength: 850 nm VCSEL-based transmission suitable for MMF deployments.
• Connector: MPO/MTP 12-fiber interface used to carry the four 10G channels across the connector assembly.
• Distance Capability: Typically up to 100 meters on standard MMF (OM3/OM4) networks, with performance dependent on fiber quality and link budget.
• Compatibility: Cisco CSR4 compliant, tested for interoperability with Arista networks and other major vendors’ switches/routers that support QSFP+ 40G uplinks.
• Form Factor: QSFP+ hot-swappable optical transceiver suitable for standard 40G ports on compatible switches and routers.
• Application Scenarios: Ideal for data center spine-leaf designs, high-density server uplinks, virtualization environments, storage area networks, and enterprise backbone connections requiring reliable 40G connectivity.

How to Install StarTech.com Cisco QSFP-40G-CSR4 Compatible QSFP+ Module

• Power down the equipment and disconnect any connected cables before handling the transceiver.
• Identify a vacant QSFP+ port on the switch or router and align the module with the slot orientation.
• Insert the QSFP+ module firmly into the port until it click-locks into place; ensure the module is seated evenly and securely.
• Connect the multimode fiber cable to the MPO/MTP connector on the transceiver, ensuring proper fiber polarity and connector cleanliness.
• Power up the device, and verify that the link status indicator shows an active connection; configure the interface as 40G (40GBASE-SR4) if required by the device.

Frequently asked questions

• Q: Is the StarTech QSFP-40G-CSR4 module truly Cisco CSR4 compatible? A: Yes. It is designed to align with Cisco CSR4 specifications while maintaining cross-vendor compatibility, including with Arista gear.
• Q: What type of fiber and connector are used? A: The module uses multimode fiber (MMF) with an MPO/MTP 12-fiber connector, optimized for 40GBASE-SR4 transmissions.
• Q: What is the expected reach? A: Typical reach is up to 100 meters on standard MMF fibers (OM3/OM4); actual distance depends on fiber quality and system requirements.
• Q: Can I mix this module with other vendors’ 40G transceivers? A: In most cases, it will work in CSR4-compatible environments but always verify vendor interoperability or run a controlled test in production to confirm stability.
• Q: How do I confirm successful installation? A: After installation, check the link status on the switch/router, verify 40GBASE-SR4 as the interface mode, and monitor for any error counters or link flaps in the interface statistics.