Single-mode SFP Vs Multimode SFP: Which One Do You Need?--ETU-LINK

The difference between multimode and single-mode SFP

August 23. 2017

Some customers want to know about the difference between multimode and single-mode SFP, so we summarize some information about multimode and single-mode optical modules.The following is some concepts and the differences between multimode and single-mode SFP transceivers.

Ⅰ. Basic Wavelength Classification For SFP Optical Modules

According to the wavelength,there are 850nm / 1310nm / 1550nm / 1490nm / 1530nm / 1610nm. 850nm wavelength is fit for multimode SFP, transmission distance is below 2KM; 1310/1550nm wavelength is fit for single-mode SFP, transmission distance is over 2KM. Generally, the SFP module price of these three wavelengths is lower than the other three.

The raw modules are easily confused if there is no identity, the manufacturers will be distinguished in the color of the ring generally. For example: The black ring is multimode and the wavelength is 850nm; The blue, yellow and purple ring is single-mode, the wavelengths are 1310nm, 1550nm, 1490nm.

SFP Optical Module Wavelength Corresponding Pull Tap Color
Wavelength	850nm	1310nm	1490nm	1550nm
Pull Tab Color	Black	Blue	Purple	Yellow	Green

10G SFP+ Optical Module Pull Tap Colors
10G SFP+ Dual-fiber Optical Module	Wavelength	850nm	1550nm	1550nm	1550nm
	Transmission	300m	10km	40km	80km
	Pull Tab Color	Black	Blue	Red	White
10G BIDI SFP+ Single-fiber BIDI Optical Module	Wavelength	TX1270nm/Rx1330nm	Tx1330nm/Rx1270nm	Tx1490nm/Rx1550nm
	Transmission	10km	10km	80km
	Pull Tab Color	Blue	Red	White

Ⅱ. What Is Multimode SFP Transceiver?

Multimode:

Almost all of the dimensions of multimode fiber core are 50/125um or 62.5/125um (multimode fiber), and the bandwidth ( the transinformations of optical fiber ) is usually 200MHz to 2GHz. Light emitting diode or laser as optical source. The ring is black color.

Single-mode:

The fiber core size of the single-mode fiber is 9/125 um,and compared with multimode fiber, it is with the features of unlimited bandwidth and lower loss. The single-mode optical transceiver used for the long-distance transmission, and sometimes up to 150-200 km. Using LD or Narrow spectral lines LED as optical source. The ring is blue, yellow or purple color.

Comparison Dimension	Multimode Fiber Optic Systems	Single-mode Fiber Optic System
Fiber Core Diameter	Thicker (50/62.5μm)	Ultra-thin (8–10μm)
Light Source and Module	Light-Emitting Diodes (LEDs) and Lasers (VCSELs)	Laser
Transmission Mode	Multiple Modes	Single-mode
Transmission Distance	Short, typically within hundreds of meters to 2 kilometers	Long, spanning tens to hundreds of kilometers
Broadband Capacity	Relatively low (declines sharply with distance)	Extremely high (supporting Tbps-level)
Bandwidth Cost	Lower initial system costs (modules, fiber)	Initially higher system costs, yet offering unlimited bandwidth potential
Typical Application	Data center rooms, buildings, enterprise campuses	Metropolitan area networks, 5G long-haul transmission, data center interconnections

Ⅲ.Key Differences & Common Mismatch Misconception

Differences and relations :

Single-mode fiber is cheap, but single-mode equipment is more expensive than the same kind of multimode equipment. Single-mode devices usually can run on single-mode fiber and can also be run on a multimode fiber, while multimode device only runs on multimode fiber. When choosing between single-mode vs multimode SFP, it's important to consider your transmission distance requirements and existing fiber infrastructure.

Golden rule: multimode SFP ↔ multimode fiber; single‑mode SFP ↔ single‑mode OS2 fiber.

Ⅳ. Practical Application Scenarios For SFP Module Selection

With the closer between single-mode and multimode SFP optical module in recent years, the use of single-mode fiber and single-mode module has become the mainstream. For applications requiring long-haul SFP transceivers, single mode is obviously better than the multimode type on the use.

1). Choose multimode SFP (850nm): Within 550m, inside data‑center racks, short LAN cabinet interconnection, cost‑sensitive short‑distance projects with existing OM1/OM2 multimode fiber infrastructure.
2). Choose single‑mode SFP (1310/1550nm): Distance over 2km, cross‑building campus, MAN access, remote base‑station connection, long‑haul fiber‑limited pipeline projects.
3). Special variant: BiDi single‑fiber SFP single‑mode modules, save half fiber cores for projects with insufficient fiber resources, must deploy in paired wavelength groups.

Ⅴ. Why Choose ETU-Link Optical Transceiver?

ETU-Link Technology Co., Ltd. offers a wide range of fiber optic SFP for sale, including both single-mode and multimode options to meet your needs. Welcome to visit our site:www.etulinktechnology.com.

As a professional manufacturer with more than 12 years of deep presence in the ‌optical communication industry‌, ETU-LINK specializes in full-series 10G/25G/100G/400G/800G optical modules and supporting optical communication devices. All our products have Compliant with FCC, CE and RoHS certifications, and are fully compatible with mainstream brand network equipment in the market.
We also support flexible OEM/ODM customization services to match diverse project requirements, with a leading 3-year warranty policy and fast order delivery.

If you are interested in our products and want to know more details, please leave a message here, or browse our product pages for [Single-mode SFP Modules] and [Multimode SFP Modules], 100% compatibility guarantee. We will reply to you as soon as we can.