Cisco SFP-10/25G-CSR-S
Dual Rate 10/25GBASE-CSR SFP Module, Original Cisco
Product Highlights
Migrating from 10G to 25G shouldn't mean ripping and replacing every optic in your infrastructure. The Cisco SFP-10/25G-CSR-S is a dual-rate SFP28 transceiver module that operates at both 10 Gigabit and 25 Gigabit Ethernet speeds over multimode fiber, giving network teams the flexibility to upgrade on their own timeline.
Operating at 850nm, this module reaches up to 300m over OM3 and 400m over OM4/OM5 multimode fiber using standard duplex LC connectors. At 25G, RS-FEC on the host port is required for full-reach operation, while 10G links require no FEC at all — making it a true drop-in replacement for legacy 10G-SR optics in environments that are transitioning to 25G.
The SFP-10/25G-CSR-S is built on the industry-standard SFP28 form factor and supports Digital Optical Monitoring (DOM) for real-time diagnostics. With a maximum power draw of just 1.2W and a commercial operating temperature range of 0°C to 70°C, it is engineered for high-density data center leaf-spine fabrics, enterprise campus aggregation, and HPC interconnects where reliability and investment protection matter most.
Features & Benefits
Dual-Rate 10G/25G Flexibility
The SFP-10/25G-CSR-S supports both 10GBASE-SR and 25GBASE-CSR Ethernet on a single module. This dual-rate capability protects your optics investment during phased 10G-to-25G migrations — deploy today at 10G and upgrade to 25G when your switches and servers are ready, without swapping transceivers.
Extended Multimode Reach
With support for up to 300m on OM3 and 400m on OM4/OM5 fiber, this module covers the vast majority of intra-building and inter-rack fiber runs. At 25G with RS-FEC enabled, you get full reach; with BASE-R FEC, the module still supports 70/100m over OM3/OM4, providing deployment flexibility even in environments without RS-FEC-capable hosts.
Digital Optical Monitoring (DOM)
Built-in DOM provides real-time telemetry on optical TX/RX power, bias current, supply voltage, and module temperature. This enables proactive fault detection and simplifies troubleshooting, reducing mean time to repair and helping network operations teams maintain SLA commitments.
Low Power, High Density
At just 1.2W maximum power consumption, the SFP-10/25G-CSR-S minimizes thermal impact in high-density switch line cards and top-of-rack deployments. Lower per-port power translates directly to reduced cooling costs and improved sustainability in large-scale data center environments.
FCoE Converged I/O
This transceiver supports Fibre Channel over Ethernet (FCoE) with appropriate host software, enabling converged data and storage traffic on a single fabric. This simplifies cabling, reduces adapter counts, and lowers overall infrastructure cost in unified data center architectures.
Deployment Scenarios
Data Center Leaf-Spine Fabric
Deploy the SFP-10/25G-CSR-S in 25G server-to-leaf uplinks within modern leaf-spine architectures. Its dual-rate capability allows mixed 10G and 25G hosts to coexist on the same leaf switches during phased server refreshes, eliminating the need for separate optic SKUs.
10G to 25G Migration
Organizations upgrading from 10G to 25G Ethernet can deploy this dual-rate module across their existing multimode fiber plant. Start at 10G today and flip to 25G as switch and NIC hardware is upgraded — no optic swap required, reducing change windows and procurement complexity.
High-Performance Computing (HPC) Interconnects
In HPC clusters where low-latency, high-bandwidth node-to-node connectivity is critical, the SFP-10/25G-CSR-S provides 25Gbps links over existing OM3/OM4 cabling. Its compact SFP28 form factor supports the dense port counts typical of HPC top-of-rack switching.
Enterprise Campus Aggregation
Use this module for 25G uplinks between campus access-layer switches and distribution/core switches. The 400m OM4 reach covers most building-to-building fiber runs within a campus, and dual-rate operation provides a cost-effective bridge during multi-year network refresh cycles.
General
Performance
Optical
Power & Environmental
Compliance & Standards
Compatibility Notes
The SFP-10/25G-CSR-S is designed for Cisco platforms with SFP28 ports that support dual-rate 10G/25G operation. Compatibility depends on switch model, line card, and software version. Always verify support using the Cisco Transceiver Compatibility Matrix before deployment.
Key deployment notes:
- 25G full reach (300m OM3 / 400m OM4): Requires RS-FEC enabled on the host port.
- 25G with BASE-R FEC: Supports 70m OM3 / 100m OM4.
- 25G without FEC: Supports 30m OM3 / 50m OM4.
- 10G operation: FEC is not required.
- Connector type: Only PC or UPC polished patch cords are supported. APC connectors are not supported.
- Interoperability note: When interoperating with IEEE 10G-SR optics, receiver overload may occur at short distances. Consult the Cisco Optics-to-Optics Interoperability Matrix at tmgmatrix.cisco.com/iop for details.
Downloads & Resources
Frequently Asked Questions
| Part Number | Product | Key Difference |
|---|---|---|
| SFP-25G-SR-S | Cisco 25GBASE-SR SFP28 Module | 25G-only (no 10G dual-rate); shorter reach — designed for short-range 25G-only deployments. |
| SFP-10/25G-LR-S | Cisco 10/25GBASE-LR SFP28 Module | Dual-rate 10G/25G over single-mode fiber (SMF) at 1310nm with up to 10km reach — choose this for long-haul links. |
| SFP-10G-SR | Cisco 10GBASE-SR SFP+ Module | 10G-only SFP+ module for MMF at 850nm — lower cost but no 25G upgrade path. |
| SFP-H25G-CU3M | Cisco 25G SFP28 DAC Cable (3m) | Passive direct-attach copper cable for ultra-short 25G links — lowest latency and cost within a single rack. |
