Cisco 40GBASE-SR4 QSFP+ Transceiver Module

The Cisco 40GBASE-SR4 QSFP+ Transceiver Module (QSFP-40G-SR4) delivers 40 Gigabit Ethernet connectivity over multimode fiber using a parallel optical architecture. The module employs four independent 10 Gbps optical lanes across an MTP/MPO-12 fiber ribbon interface, aggregating to a full 40 Gbps duplex data path. Designed to the IEEE 802.3ba 40GBASE-SR4 standard, it operates over OM3 multimode fiber at distances up to 100 meters and over OM4 multimode fiber at distances up to 150 meters, making it well-suited for structured cabling plants already deployed in enterprise data centers.

The transceiver uses 850 nm VCSEL (Vertical-Cavity Surface-Emitting Laser) technology across all four transmit lanes, with a corresponding four-lane receiver array. The hot-swappable QSFP+ form factor integrates directly into Cisco Nexus, Catalyst, and MDS platforms that carry compatible QSFP+ ports, allowing non-disruptive insertion and removal without powering down the host system. Digital Optical Monitoring (DOM) support provides real-time visibility into transmit power, receive power, temperature, and supply voltage directly from the host platform's management interface.

This module occupies a key position in aggregation layer deployments where existing OM3 or OM4 multimode fiber infrastructure is already in place, eliminating the need to re-fiber for 40G upgrades. It is particularly effective for migration scenarios where 40G uplinks bridge legacy 10G access tiers to higher-capacity core segments, and for inter-rack connections within the same data center facility. The module is manufactured and tested by Cisco and is identified by Cisco's internal product identification for full compatibility enforcement on Cisco-branded switching and routing hardware.

Ideal for

• Aggregation uplinks connecting 10G access-layer Cisco Nexus switches to 40G distribution or core switches over existing OM3/OM4 fiber plant
• Top-of-rack to end-of-row interconnects within the same data center row where multimode fiber runs are under 100 meters
• Storage area network (SAN) director-to-director inter-switch links on Cisco MDS 9000 series platforms requiring high-density 40G MMF connectivity
• Data center migration projects upgrading backbone segments from 10G to 40G without replacing installed multimode fiber cabling infrastructure
• High-density server cluster interconnects in HPC or virtualization environments where parallel 40G MMF links reduce east-west latency
• Lab and test environment backbone links where short-reach multimode connectivity supports traffic simulation and network validation at 40G line rate

Technical specifications

Available from Omnixon Global. Submit an RFQ and our team will confirm configuration and availability for your order.