Just to confirm, does this duplex LC transceiver require OM2 multi-mode fiber, or can I use it with my existing OM1 or OM3 MMF patch cables?

You can use it with OM1, OM2, OM3, or OM4 MMF! While the maximum 550m transmission distance is officially rated over OM2/OM3, it's fully backwards compatible with older OM1 cables (though the max distance will drop to around 275m).

Hello sir, will this LS-MM851G-S5C plug and play with Cisco Catalyst 9300 series? Also, does it trigger any unsupported transceiver warnings?

Yes, it is 100% MSA compliant and thoroughly tested for OEM compatibility with Cisco switches, including the Catalyst 9300. It functions just like the original GLC-SX-MMD, so you won't see any "unsupported transceiver" error logs in your CLI.

The specs say this is a commercial 0 to 70°C module. Do you have an industrial version of this exact 850nm SFP that can survive in an outdoor telecom cabinet?

Good question! This commercial-grade model handles indoor data centers and AC-cooled racks perfectly. For harsh outdoor environments or cell tower backhaul, we recommend our industrial-grade counterpart (LS-MM851G-S5I), which supports extreme temperatures from -40°C to 85°C.

We require full DOM/DDM for our network monitoring system. Does this module support SFF-8472 protocol for tracking TX/RX power and temperature?

Yes, indeed! The LS-MM851G-S5C features built-in Digital Optical Monitoring (DOM) compliant with the SFF-8472 protocol. It allows your sysadmins to monitor real-time diagnostics like temperature, voltage, laser bias current, and TX/RX optical power directly from your switch interface.

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Juniper EX-SFP-1GE-SX Compatible LINK-PP 1G SFP 850nm 550m Duplex LC DOM MMF Optical Transceiver Module

Name: Juniper EX-SFP-1GE-SX Compatible LINK-PP 1G SFP 850nm 550m Duplex LC DOM MMF Optical Transceiver Module
Brand: LINK-PP
SKU: 212771
Price: 6.012 USD
Availability: InStock
Rating: 4.9 (30 reviews)

# 212771

Product: Juniper EX-SFP-1GE-SX Compatible LINK-PP 1G SFP 850nm 550m Duplex LC DOM MMF Optical Transceiver Module
SKU: 212771
P/N: LS-MM851G-S5C
Price: $ 6.99
Stock: 317 in Stock
Sold: 2K
Product URL: https://www.l-p.com/products/482246.htm

For Order Over $1000 Get $15.00 Off , Code: Linkpp15

For Order Over $3000 Get $50.00 Off , Code: Linkpp50

For Order Over $5000 Get $100.00 Off , Code: Linkpp100

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Manufacture: LINK-PP

P/N: LS-MM851G-S5C

Compatible:: Cisco; LINK-PP; Adtran; Alcatel-Lucent; Allen-Bradley; Allied Telesis; Arista; Avago; Avaya; Broadcom; Brocade; Calix; Ciena; D-Link; DELL; Extreme; F5 Networks; FS; Force10; Fortinet; Generic; H3C; HPE; HPE Aruba; HPE H3C; HPE ProCurve; IBM; Intel; Juniper; NVIDIA/Mellanox; Netgear; Palo Alto Networks; Planet; ProCurve; SMC Networks; TRENDnet; Ubiquiti

Compatible P/N:: EX-SFP-1GE-SX | 550m; EX-SFP-1GE-SX-ET | 550m; SFP1G-SX-31 | 2km; SFP1G-SX-31-I | 2km

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Juniper EX-SFP-1GE-SX Compatible LINK-PP 1G SFP Specifications

The Juniper EX-SFP-1GE-SX Compatible LINK-PP module is a high-performance, commercial-grade SFP transceiver delivering data rates up to 1.25 Gbps. Featuring an 850nm VCSEL transmitter and a duplex LC interface, it operates efficiently over multi-mode fiber for distances up to 550 meters. Complete with digital optical monitoring support, it ensures reliable and stable gigabit network connectivity.

Juniper Part Number	EX-SFP-1GE-SX	Vendor Name	LINK-PP
Form Factor	SFP	Max Data Rate	1.25Gbps
Wavelength	850nm	Max Cable Distance	550m over OM2 MMF
Connector	Duplex LC	Media	MMF
Transmitter Type	VCSEL	Receiver Type	PIN
TX Power	-9 to 0dBm	RX Power	-20 to -1dBm
Receiver Sensitivity	-18dBm	DOM Support	Yes
Operating Temperature Range	0 to 70°C	Protocols	IEEE 802.3z, SFF-8472, FC-PI, SFP MSA (INF-8074i) Compliant

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Q: Just to confirm, does this duplex LC transceiver require OM2 multi-mode fiber, or can I use it with my existing OM1 or OM3 MMF patch cables? By D***n on 2026-05-05

A: You can use it with OM1, OM2, OM3, or OM4 MMF! While the maximum 550m transmission distance is officially rated over OM2/OM3, it's fully backwards compatible with older OM1 cables (though the max distance will drop to around 275m). By admin on 2026-05-05
Q: Hello sir, will this LS-MM851G-S5C plug and play with Cisco Catalyst 9300 series? Also, does it trigger any unsupported transceiver warnings? By B***n on 2026-04-28

A: Hi! Yes, it is 100% MSA compliant and thoroughly tested for OEM compatibility with Cisco switches, including the Catalyst 9300. It functions just like the original GLC-SX-MMD, so you won't see any "unsupported transceiver" error logs in your CLI. By admin on 2026-04-28
Q: The specs say this is a commercial 0 to 70°C module. Do you have an industrial version of this exact 850nm SFP that can survive in an outdoor telecom cabinet? By S***n on 2025-11-16

A: Good question! This commercial-grade model handles indoor data centers and AC-cooled racks perfectly. For harsh outdoor environments or cell tower backhaul, we recommend our industrial-grade counterpart (LS-MM851G-S5I), which supports extreme temperatures from -40°C to 85°C. By admin on 2025-11-16
Q: I need to deploy around 300 of these 1G SFP transceivers for a new campus network build. Is there any B2B bulk pricing or discount code available? By A***n on 2025-10-19

A: Absolutely. For enterprise procurement and data center mass deployments, we offer tiered volume discounts. You can check the bulk rates directly on the product page, or contact our sales team via Live Chat for a custom quote on your 300-piece order! By admin on 2025-10-19
Q: We require full DOM/DDM for our network monitoring system. Does this module support SFF-8472 protocol for tracking TX/RX power and temperature? By K***r on 2025-08-15

A: Yes, indeed! The LS-MM851G-S5C features built-in Digital Optical Monitoring (DOM) compliant with the SFF-8472 protocol. It allows your sysadmins to monitor real-time diagnostics like temperature, voltage, laser bias current, and TX/RX optical power directly from your switch interface. By admin on 2025-08-15

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M***z

Argentina

Verified Purchase

5 .0

2026-05-25

Best value 1G MMF transceivers for data center mass deployment. Will order more.

81 Helpful vote Comments

B***s

Italy

Verified Purchase

5 .0

2026-04-08

Replaced old modules with this LS-MM851G-S5C. The duplex LC interface clicked perfectly into place.

248 Helpful vote Comments

J***z

Kenya

Verified Purchase

5 .0

2025-11-22

Awesome OEM compatibility! Linked my Dell core switch to a Ubiquiti edge router seamlessly.

146 Helpful vote Comments

B***n

Macao

Verified Purchase

5 .0

2025-11-22

Solid MSA compliant SFP, plug and play!

150 Helpful vote Comments

E***e

United Kingdom

Verified Purchase

4 .0

2025-11-02

Packaging was excessive for these transceivers, though the 850nm SFP performance is solid.

133 Helpful vote Comments

C***s

Norway

Verified Purchase

5 .0

2025-07-20

No issues syncing at 1.25Gbps on Aruba.

233 Helpful vote Comments

P***r

India

Verified Purchase

5 .0

2025-07-14

Deployed these gigabit transceivers for a multi-building fiber campus network. The 550m distance spec is conservative; we pushed solid speeds without signal degradation. Essential gear for any serious data center!

235 Helpful vote Comments

D***s

Belgium

Verified Purchase

5 .0

2025-06-19

I'm a network engineer managing a large enterprise rollout. Tested these LS-MM851G-S5C modules across multiple Cisco and Arista switches. The DOM readings are spot-on, and OM2 MMF links remain rock-solid.

186 Helpful vote Comments

B***a

Belgium

Verified Purchase

5 .0

2025-05-25

Flawless Cisco compatible 1G SFP module connection.

103 Helpful vote Comments

K***n

France

Verified Purchase

5 .0

2025-05-16

Great price for bulk 1.25G SFP transceivers.

133 Helpful vote Comments

K***n

Ukraine

Verified Purchase

5 .0

2025-05-15

Fast 850nm transceiver, DOM feature is super handy.

237 Helpful vote Comments

M***r

United States

Verified Purchase

5 .0

2025-05-09

Good duplex LC SFP for home NAS.

212 Helpful vote Comments

S***t

Spain

Verified Purchase

5 .0

2025-04-25

Excellent IEEE 802.3z compliant gigabit solution. My Juniper switch recognized the transceiver right away!

246 Helpful vote Comments

J***n

Colombia

Verified Purchase

5 .0

2025-03-18

Upgraded our campus networking setup. The 550m transmission distance is perfectly accurate!

163 Helpful vote Comments

A***h

Greece

Verified Purchase

4 .0

2025-01-04

The 1G SFP modules work flawlessly, but the outer shipping box arrived slightly crushed.

103 Helpful vote Comments

D***n

Venezuela

Verified Purchase

5 .0

2024-11-07

Used for local distribution frames. The commercial 0-70°C temp range handles indoor racks well.

146 Helpful vote Comments

S***n

Dominican Republic

Verified Purchase

5 .0

2024-10-30

Needed a cost-effective alternative for Fortinet and HPE ProCurve switches. These 1G SFP 850nm transceivers delivered immediately. Excellent SFF-8472 protocol support, and the low power consumption keeps 48-port racks cool. ❄️

99 Helpful vote Comments

J***e

United States

Verified Purchase

5 .0

2024-09-03

Best shipping experience in the inter webs

52 Helpful vote Comments

V***v

Malaysia

Verified Purchase

5 .0

2024-08-09

Thanks, good price and Fast respond. Wait for the next order.

56 Helpful vote Comments

M***o

United States

Verified Purchase

5 .0

2024-05-17

I ordered equipment from LINK-PP.COM regularly and they always deliver. I have not had a bad or missed order and everything is in good condition. Turnaround times are Fast and expectations are always met. That's why I choose it.

41 Helpful vote Comments

J***t

Nepal

Verified Purchase

5 .0

2024-04-03

Great service. Easy ordering online.

47 Helpful vote Comments

A***L

Netherlands

Verified Purchase

5 .0

2024-02-25

Super Product, will buy again.

47 Helpful vote Comments

T***d

United States

Verified Purchase

5 .0

2023-12-13

installed a couple days ago on our test bed, seems to work perfectly fine.Will probably buy again

63 Helpful vote Comments

J***n

United States

Verified Purchase

5 .0

2023-11-18

Pleasantly surprised to get the best price from l-p.com

47 Helpful vote Comments

R***n

United States

Verified Purchase

5 .0

2023-11-17

I am very pleased with how easy it is to find everything I need on the site. It is Fast and works well with purchases through my PayPal account. Glad to see l-p.com is utilizing the latest payment methods.

43 Helpful vote Comments

C***s

Ireland

Verified Purchase

5 .0

2023-10-11

It was shipped in 3 days. Product was packed very well and quality is the best. Thank you !

46 Helpful vote Comments

V***a

United States

Verified Purchase

5 .0

2023-06-19

It came sooner than I expected!

48 Helpful vote Comments

H***n

Turkey

Verified Purchase

5 .0

2023-04-20

Great price and quick shipping. Great seller.

31 Helpful vote Comments

R***f

Japan

Verified Purchase

5 .0

2023-03-20

Very nice variety of products. Prices are great

56 Helpful vote Comments

M***z

Taiwan, Province of China

Verified Purchase

5 .0

2023-01-18

I am very pleased with the quality of products. The product arrived for two weeks at the given address. The seller is very kind and reliable, I recommend to everyone!!!

48 Helpful vote Comments