Single-mode SFP VS Multimode SFP: What’s the Difference?
Recently, in our communication with customers, we found that customers are often confused about the choice between single-mode and multi-mode SFP, so we feel it is necessary to write an article to analyze their characteristics in detail, hoping to help everyone.
What is Single-mode SFP?
The single-mode SFP module uses a single-mode laser inside, and its emission wavelength is 1310nm band or 1550nm band, and the transmission uses single-mode optical fiber with a core diameter of 9um.
What is Multimode SFP?
The multi-mode SFP module uses a multi-mode laser inside, its emission wavelength is 850nm band, and the transmission uses single-mode fiber with a core diameter of 50um.
Single-mode SFP VS Multimode SFP: What’s the Difference?
Working Wavelength
The emission wavelength of single-mode SFP is 1310nm band or 1550nm band
The emission wavelength of multi-mode SFP is 850nm band
Color Coding
The color of the single-mode SFP pull ring varies according to the transmission distance of the module, blue is 10km, red is 40km, and white is 80km;
The color of the multi-mode SFP pull ring is black, and the transmission distance is 500m
Transmitter
Single-mode SFP uses single-mode lasers. According to the laser structure type, there are FP lasers, DFP lasers and DBR lasers; according to the modulation type, there are DML lasers and EML lasers.
Multimode SFP uses VCSEL laser, which has a relatively wide spectrum and can only be used for short-distance transmission.
Cost
The price of single-mode SFP is relatively high, which also depends on the transmission distance
Multi-mode SFP prices are relatively low
How to buy And Use Single Mode SFP & Multimode SFP?
Tips on Utilizing Single-mode SFP and Multimode SFP
The applications of single-mode and multi-mode SFP are similar. The difference mainly depends on the transmission distance. If the transmission distance is less than 500m, you can use multi-mode SFP. If the distance is longer, choose single-mode SFP.
Conclusion
In short, single-mode and multi-mode SFP have their own characteristics. Users need to choose which SFP to use based on project requirements such as transmission distance and project budget.
FAQs
Can I use multimode fiber with single-mode SFP?
The core diameters of multimode fiber and single-mode SFP do not match, and cross-use will cause greater losses. At the same time, the transmission bandwidth of multi-mode fiber is relatively low, which limits the transmission distance of single-mode SFP. It is not recommended to use it in this way.
Can I use Multimode SFP with Single-Mode Fiber?
The core diameters of multimode SFP and single-mode optical fiber do not match, and cross-use will cause greater loss and cannot be used in this way.
Is multimode fiber cheaper than single-mode?
Although the price of multi-mode SFP is lower than that of single-mode SFP, the unit price of multi-mode fiber is higher than that of single-mode fiber because the core diameter of multi-mode fiber is thicker and the refractive index of the core is gradient, making it more difficult to manufacture. high.
What is the minimum distance for single-mode SFP?
There is generally no minimum transmission distance requirement for single-mode SFP, but the receiving sensitivity of long-distance SFP modules is high. Too much input optical power at the receiving end can easily cause permanent failure of the receiving end. When using short-fiber direct connection, an optical attenuator needs to be added to ensure The input optical power at the receiving end is within the nominal range of the specification.
How far can multimode fiber go?
The maximum transmission distance of multi-mode SFP is also related to the speed of the module. The transmission distance of 2.5Gbps multi-mode SFP is about 500m, and the transmission distance of 10Gbps multi-mode SFP is 300m.
Can I use Single Mode SFP and Multimode SFP interchangeably?
On the host interface, single-mode SFP and multi-mode SFP are interchangeable. On the optical port side, the transmission distance and type of optical fiber used need to be considered.
Can I upgrade from Multimode to Single Mode SFPs without altering my existing infrastructure?
In terms of network structure, multi-mode SFP can be replaced with single-mode SFP, and multi-mode optical fiber needs to be replaced with single-mode optical fiber.
What is the acceptable dB loss for single mode fiber?
In the 1310nm band, the loss of single-mode fiber is no higher than 0.35dB/km, and in the 1550nm band, the loss of single-mode fiber is no higher than 0.2dB/km, both of which are acceptable.
What is the acceptable dB loss for multimode fiber?
Multimode optical fiber is acceptable if the distance is short and the total loss is no higher than 3dB.
How do you identify single-mode and multimode fiber?
The colors of the protective covers of single-mode optical fiber and multi-mode optical fiber are different. The protective cover of single-mode optical fiber is yellow, and the protective cover of multi-mode optical fiber is orange, light blue or purple.
Can I use single mode fiber for a short distance?
Single-mode fiber can be used for short-distance transmission
Can multimode fiber support 10gb?
Multimode fiber can support transmission rates of 10Gbps
Can a multimode transceiver be used with single mode fiber?
The short answer is no，because such a connection solution is unreliable, will cause large optical degradation and data loss, and may even cause damage to related equipment，the results may be unpredictable.
Is single mode better than multimode fiber?
The selection of single-mode fiber and multi-mode fiber depends on the transmission distance and cost, and has nothing to do with the quality of the fiber.
