SFP-10G-SR vs SFP-10G-LRM vs SFP-10G-LR, Which to Choose?
Mar 30, 20221 min read
In 10G Ethernet deployments, three 10G SFP+ transceiver types are most commonly used: SFP-10G-SR, SFP-10G-LRM, and SFP-10G-LR. Each module is designed for different fibre distances and environments, making it important to understand their characteristics before selecting the appropriate option for your network.
Understanding SFP-10G-SR, SFP-10G-LR and SFP-10G-LRM Optical Modules
SFP refers to a small form-factor module that can be hot-pluggable. 10G stands for their maximum transmission rate of 10.3 Gbps suitable for 10 Gigabit Ethernet. SR, LRM, LR represent the transmission distance of the 10G optical module. The transmission distance they represent is from short to long.
SR, LRM, and LR differ not only in reach, but also in fiber compatibility, laser technology, and typical usage scenarios. Below is a concise breakdown of what sets them apart.
SFP-10G-SR
The SFP-10G-SR is a 10GBASE-SR SFP+ module, which can reach up to 300 meters matched with OM3 Multimode Fiber (MMF), known as the lowest-cost, lowest-power modules implemented with a VCSEL. Commonly used in data centres and high-density multimode applications.
SFP-10G-LR
The SFP-10G-LR is a 10GBASE-LR SFP+ module that adopts a Distributed Feedback Laser (DFB). It operates at a nominal wavelength of 1310nm and can reach up to 10 km over Single Mode Fiber (SMF). It is used in wiring buildings on a large campus or even setting up a Metro Area Network (MAN).
SFP-10G-LRM
The SFP-10G-LRM is a 10GBASE-LRM module that supports link lengths of 220m on standard Fiber Distributed Data Interface (FDDI) grade multimode fiber. To ensure that specifications are met over FDDI-grade, OM1 and OM2 fibers, the transmitter should be coupled through a mode conditioning patch cord. No mode conditioning patch cord is required for applications over OM3 or OM4.
SFP-10G-SR | SFP-10G-LR | SFP-10G-LRM |
Form Factor | SFP+ | SFP+ | SFP+ |
Interface | LC duplex | LC duplex | LC duplex |
Max. Power Consumption | ≤1W | ≤1W | ≤1W |
Commercial Temperature | 0～ 70°C (32 ～ 158°F) | 0～ 70°C (32 ～ 158°F) | 0～ 70°C (32 ～ 158°F) |
DOM | YES | YES | YES |
Wavelength | 850nm | 1310nm | 1310nm |
Laser Type | VCSEL 850nm | DFB 1310nm | FP 1310nm |
Cable Type | MMF | SMF | SMF/MMF |
Max. Cable Distance | 300m/400m | 10km | 220m/300m |
Rate | 10 Gbps | 10 Gbps | 10 Gbps |
TX Power | -7.3～-1dBm | -8.2～0.5dBm | -6.5~-0.5dBm |
Receiver Sensitivity | < -11.1dBm | < -14.4dBm | < -8.4dBm |
Application Range | Only used for short distance connections | Only used for long distance connections | Only used for short distance connections |
Comparison: SFP-10G-SR vs SFP-10G-LR vs SFP-10G-LRM
From the table above, it's clear that these three 10G SFP+ modules share similar basic functions, but they differ in wavelength, fiber type, and transmission distance. To make the selection easier, the following sections compare SFP-10G-LRM vs. SFP-10G-SR, SFP-10G-LRM vs. SFP-10G-LR, and SFP-10G-SR vs. SFP-10G-LR, outlining their use cases and helping you choose the right module for your network.
SFP-10G-SR vs SFP-10G-LRM
SFP-10G-SR transceivers and SFP-10G-LRM transceivers both support multimode fiber transmission. The former supports 300m over OM3 cable and 400m over OM4 cable, while the latter supports 200m over OM3 or OM4 cable. Normally, when the transmission distance is less than 300 meters, SFP-10G-SR is recommended. However, if you have other requirements, for example, 200m transmission with modal bandwidth of 500 MHz km, then an SFP-10G-LRM transceiver is necessary. For more subtle differences, refer to the following chart:
Modules | Wavelength (nm) | Cable Type | Core Size (Microns) | Modal Bandwidth (MHz km) |
SFP-10G-SR | 850 | MMF | 62.5 | 160 (FDDI) |
62.5 | 200 (OM1) | |||
50 | 400 | |||
50 | 500 (OM2) | |||
50 | 2000 (OM3) | |||
50 | 4700 (OM4) | |||
SFP-10G-LRM | 1310 | MMF | 62.5 | 500 |
50 | 400 | |||
50 | 500 |
SFP-10G-LR vs SFP-10G-LRM
The SFP-10G-LR transceiver operates at 1310 nm and supports single-mode fiber. It offers a typical reach of up to 10 km, making it suitable for building-to-building links, campus networks, and metro-access connections.
The SFP-10G-LRM transceiver also operates at 1310 nm but supports both multimode and short-reach single-mode fiber. It reaches up to 220 meters on OM3 and up to 300 meters on single-mode fiber. It is designed for short-range upgrades inside data centers or buildings, especially when existing multimode cabling needs to be reused for 10G. For single-mode links under 300 meters, the SFP-10G-LRM is a cost-effective option. For 2–10 km links, the SFP-10G-LR is the only suitable choice.
SFP-10G-SR vs SFP-10G-LR
Both SFP-10G-SR and SFP-10G-LR are 10G SFP+ modules and use an LC duplex interface, but they differ in fiber type and transmission distance. The SFP-10G-SR uses an 850 nm wavelength and runs on multimode fiber. It supports up to 300 meters on OM3 and up to 400 meters on OM4, making it ideal for short-distance links inside data centers and between racks.
The SFP-10G-LR uses a 1310 nm wavelength and supports only single-mode fiber, with a typical reach of up to 10 km. It is widely used for building-to-building, campus, and metro-area links. In general, SFP-10G-SR is preferred for short-reach connections inside data centers, while SFP-10G-LR is the standard choice for single-mode links across buildings or campus networks.
To learn more about SFP+ 10G SR and SFP+ 10G LR modules, check out our guide: Short-Range vs. Long-Range 10G Optical Modules: How to Choose?
FS 10G Optical Modules: Reliable Options
After comparing these 10G SFP+ options, it becomes clear that different modules fit different deployment scenarios. This is also why choosing a vendor with a complete 10G portfolio can simplify planning and ensure long-term scalability.
FS offers a full range of 10G SFP+ transceivers—including SR, LRM, and LR—designed for data centers, campus networks, and enterprise applications. These modules are tested on major switch platforms and follow industry standards, making them a reliable choice for diverse network environments.
Modules | Product Highlights |
 | Max. Power Consumption 1W, and TO Packaging Features High Reliability Supports up to 400m over OM4 and 300m over OM3 via LC Duplex Small 10G Form Factor for Greatest Density per Chassis Support 4x10G Fan out and Easy Migration to 40G Platforms FS BOX - Support Real-time Configuration Hot Pluggable SFP+ MSA and RoHS Compliant Optical Interoperability with 10GBASE XENPAK, X2, and XFP Interfaces On the Same Link Digital optical monitoring capability for strong diagnostic capabilities |
 | Built-in Semtech Chip, Max. Power Consumption 1W Supports up to 10km Transmission over LC Duplex SMF Hot Pluggable SFP+ MSA Compliant FS BOX - Support Real-time Configuration Optical Interoperability with 10GBASE XENPAK, X2, and XFP Interfaces On the Same Link TO Package Features High Reliability and Robust Physical Protection Class 1 FDA Laser Safety and RoHS Compliant IEEE 802.3ae Compliant |
 | Built-in Semtech Chip, Max. Power Consumption 1W Supports up to 220m over OM3 and 300m over OM4 MMF Hot Pluggable SFP+ MSA Compliant FS BOX - Support Real-time Configuration Optical Interoperability with 10GBASE XENPAK, X2, and XFP Interfaces On the Same Link TO Package Features High Reliability and Robust Physical Protection Class 1 FDA Laser Safety and RoHS Compliant IEEE 802.3ae Compliant |
Conclusion
Overall, the choice of 10G optical modules can be quickly determined based on link distance and fiber type: for short-distance links within data centers or racks using OM3/OM4 multimode fiber, SFP-10G-SR is the preferred option; if you need a module that covers both short-reach multimode and short-reach single-mode links, SFP-10G-LRM is suitable; for single-mode fiber links ranging from a few hundred meters up to several kilometers (typically 2–10 km), SFP-10G-LR is the most reliable choice.
For precise selection based on specific link parameters and device compatibility, consult FS technical experts to get a customized solution.