Cisco QSFP-40G-SR4 Transceiver

Cisco QSFP-40G-SR4 – High-Performance 40G Transceiver for Short-Range Fiber Networks

The Cisco QSFP-40G-SR4 is a powerful 40 Gigabit Ethernet transceiver module designed for short-range, high-speed optical communication over multimode fiber (MMF). Operating at 850nm, it supports up to 100 meters using OM3 and up to 150 meters over OM4 fiber. Ideal for enterprise core switches, data centers, and high-performance aggregation layers, the Cisco QSFP-40G-SR4 enables efficient 40G connectivity through a compact QSFP+ form factor.

Its plug-and-play functionality, combined with Cisco’s robust hardware ecosystem, ensures seamless integration across a variety of platforms including Nexus, Catalyst, and UCS systems. Whether you’re upgrading to 40G or interconnecting high-density systems, this module is optimized for reliability, flexibility, and low power consumption.

Key Features of Cisco QSFP-40G-SR4

• Data Rate: 40 Gbps (4 x 10G parallel channels)

• Interface: MPO-12 connector

• Reach: Up to 150m over OM4, 100m over OM3

• Wavelength: 850nm

• Form Factor: QSFP+ (Quad Small Form-Factor Pluggable Plus)

• Hot-swappable: Yes

• Low Power Consumption: Less than 1.5W

• Compatibility: Cisco Nexus, Catalyst, UCS Fabric Interconnects

• Standards: IEEE 802.3ba, MSA-compliant

Why Choose Cisco QSFP-40G-SR4?

The Cisco QSFP-40G-SR4 delivers ultra-fast connectivity with minimal latency, making it ideal for high-performance applications such as virtualized environments, cloud computing platforms, and massive data transfers. Its MPO interface provides a simple, scalable way to connect QSFP+ ports using pre-terminated fiber cabling. This ensures simplified deployment, especially in environments that require quick scaling and minimal cabling complexity.

Choosing this transceiver also guarantees full compatibility with Cisco’s operating systems and diagnostic tools, allowing IT teams to manage and monitor transceiver health, power levels, and signal quality in real time using DOM (Digital Optical Monitoring).

Use Cases for Cisco QSFP-40G-SR4

The Cisco QSFP-40G-SR4 is suited for:

• High-speed aggregation between Cisco Nexus core switches

• Uplink modules for Cisco Catalyst access switches

• East-west traffic within modern leaf-spine data center topologies

• Inter-rack connections using MPO cabling

• Backbone links in high-density enterprise environments

Its support for multimode fiber makes it a cost-effective choice for short-range connectivity where long-haul optics are not required.

Deployment Flexibility with Cisco QSFP-40G-SR4

One of the standout advantages of the Cisco QSFP-40G-SR4 is its versatility in deployment. Whether you’re managing a small-scale data center or a massive cloud infrastructure, this transceiver adapts to your architecture. Its ability to support both point-to-point and breakout configurations (4x10G) makes it an extremely flexible solution.

For example, using breakout cables, a single Cisco QSFP-40G-SR4 can be connected to four 10G SFP+ ports, allowing backward compatibility and better bandwidth distribution across your network. This makes it an excellent option for gradual upgrades, where 10G infrastructure is still in place but expansion toward 40G is underway.

In addition, thanks to its hot-swappable nature, the transceiver can be replaced or added without interrupting the system or requiring a reboot—essential in live production environments where uptime is critical.

Performance in High-Density Environments

As enterprises and service providers push for more throughput and compact designs, the Cisco QSFP-40G-SR4 stands out due to its high-density capabilities. Each QSFP+ port can accommodate a full 40G link, reducing the number of ports and cables required compared to multiple 10G links. This significantly simplifies cable management and reduces clutter, especially in racks with hundreds of links.

Moreover, the transceiver’s low power consumption—under 1.5W—means lower operational costs in cooling and energy use, which adds up considerably in data centers operating at scale. The result is a greener, more efficient, and more manageable environment that still delivers top-tier speed and performance.

Reliable Cisco Compatibility and Support

Choosing the Cisco QSFP-40G-SR4 isn’t just about speed—it’s also about trust and integration. This module is fully tested and certified by Cisco to work with their Nexus, Catalyst, and UCS product lines. It integrates seamlessly with Cisco IOS and NX-OS environments, giving IT teams full visibility into transceiver health via Digital Optical Monitoring (DOM) tools.

With Cisco support and warranty behind the Cisco QSFP-40G-SR4, network engineers can rely on robust documentation, updates, and replacement support, reducing troubleshooting time and long-term maintenance costs.

Enhanced Network Scalability

Network growth requires components that can scale with demand, and the Cisco QSFP-40G-SR4 is built with that scalability in mind. Whether you’re increasing bandwidth within your spine-leaf fabric or expanding across multiple racks and zones, this transceiver provides a scalable and standardized path forward.

Its use of multimode fiber and MPO-12 connectors supports rapid deployment using pre-terminated cables, eliminating the time-consuming splicing and manual termination often required with legacy fiber systems.

With the ability to support short-reach optical connectivity up to 150 meters over OM4, the Cisco QSFP-40G-SR4 is perfect for interconnecting high-performance servers, storage arrays, and virtualized applications with minimal latency.

Future-Proofing Your Network

As network demands increase due to cloud migration, IoT integration, and remote workforce expansion, upgrading your data infrastructure becomes inevitable. The Cisco QSFP-40G-SR4 allows businesses to prepare for the future by providing high-speed performance today with the flexibility to adapt tomorrow.

Its support for both native 40G and backward-compatible 10G configurations makes it future-ready. Whether you’re fully transitioning to 40G or maintaining a hybrid setup, this transceiver ensures your investment remains relevant for years.