What type of fiber optic cable does this module require?

It requires a standard single-mode fiber (SMF) cable with duplex LC connectors.

What is the maximum transmission distance for this transceiver?

This optical module supports a maximum transmission distance of up to 2km.

Does the SFP1G-SX-31 support real-time diagnostic monitoring?

Yes, it features integrated Digital Diagnostic Monitoring (DDM/DOM) via an I2C interface.

What is the maximum data rate supported by this SFP module?

It supports up to 1.25Gbps for Gigabit Ethernet and Fiber Channel.

Aside from standard Gigabit Ethernet, can we use this SFP module for our Storage Area Network (SAN) upgrade?

Yes! Besides standard IEEE 802.3ah-2004 for Gigabit Ethernet, this module fully supports 1.063Gbps Fiber Channel protocols, making it a highly reliable and cost-effective solution for upgrading enterprise SANs and NAS storage environments.

We use a mix of Cisco Catalyst and Dell switches in our racks. Will this 1.25G SFP module work seamlessly across different brands?

Yes! The LS-SM311G-02C is fully SFF-8472 MSA compliant and features broad OEM compatibility. It has been strictly tested by our engineers to work perfectly with Cisco, Dell, Juniper, Arista, and other major switch brands without throwing any protocol errors.

We are planning to use these in an outdoor cabinet for a base station backhaul. Does this commercial 0-70°C version work, or do you have an industrial wide-temperature option?

For outdoor cabinets, we highly recommend our industrial version, the LS-SM311G-02I, which supports extreme temperatures from -40°C to 85°C. This commercial LS-SM311G-02C model (0 to 70°C) is specifically designed for indoor data centers, campus LANs, and enterprise server rooms.

To reach the maximum 2km transmission distance, what exact type of fiber optic patch cables should we purchase?

To achieve the full 2km link safely, you need standard Single-Mode Fiber (SMF) with Duplex LC connectors. Ensure your patch cables match the 1310nm wavelength and 9/125µm core size for optimal Tx/Rx optical power performance.

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Cisco SFP1G-SX-31 Compatible LINK-PP 1.25G SFP 1310nm 2km Duplex LC DOM SMF Optical Transceiver Module

Name: Cisco SFP1G-SX-31 Compatible LINK-PP 1.25G SFP 1310nm 2km Duplex LC DOM SMF Optical Transceiver Module
Brand: LINK-PP
SKU: 212630
Price: 4.73 USD
Availability: InStock
Rating: 5 (35 reviews)

# 212630

Product: Cisco SFP1G-SX-31 Compatible LINK-PP 1.25G SFP 1310nm 2km Duplex LC DOM SMF Optical Transceiver Module
SKU: 212630
P/N: LS-SM311G-02C
Price: $ 5.5
Stock: 1081 in Stock
Sold: 945
Product URL: https://www.l-p.com/products/494856.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-SM311G-02C

Compatible:: Cisco; LINK-PP; Adtran; Alcatel-Lucent; Allied Telesis; Arista; Avaya; Brocade; Calix; Ciena; D-Link; Dell; Extreme; FS; Fortinet; Generic; H3C; IBM; Intel; Juniper; NVIDIA/Mellanox; Netgear

Compatible P/N:: SFP1G-SX-31 | 2km; SFP1G-SX-31-I | 2km; GLC-LH-SM | 10km; GLC-LH-SMD | 10km; GLC-LH-SM-20 | 20km; GLC-LX-SM-RGD | 20km; GLC-EX-SM1550-40 | 40km; GLC-EX-SMD | 40km; MGBLH1 | 40km; GLC-ZX-SM | 80km; GLC-ZX-SM-RGD | 80km; GLC-EZX-SM-100 | 100km; GLC-EZX-SM-120 | 120km; GLC-EZX-SM-160 | 160km

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Cisco SFP1G-SX-31 Compatible LINK-PP 1.25G SFP Specifications

The Cisco SFP1G-SX-31 Compatible LINK-PP module is a high-performance Small Form-factor Pluggable (SFP) transceiver module engineered for reliable 1.25Gbps data communications over single-mode fiber. This hot-pluggable module fully complies with SFP MSA and SFF-8472 industry specifications. Operating under a single +3.3V power supply, it features a stable 1310nm FP laser transmitter and integrated digital diagnostic monitoring functions.

Cisco Part Number	SFP1G-SX-31	Vendor Name	LINK-PP
Form Factor	SFP	Max Data Rate	1.25Gbps
Wavelength	1310nm	Max Cable Distance	2km
Connector	Duplex LC	Media	SMF
Transmitter Type	FP	Receiver Type	PIN
TX Power	-12 to -3dBm	RX Power	-23 to -1dBm
Receiver Sensitivity	<-23dBm	DOM Support	Yes
Operating Temperature Range	0 to 70°C	Protocols	SFF-8472 MSA Compliant, IEEE 802.3ah-2004

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Q: Aside from standard Gigabit Ethernet, can we use this SFP module for our Storage Area Network (SAN) upgrade? By D***z on 2026-05-09

A: Yes! Besides standard IEEE 802.3ah-2004 for Gigabit Ethernet, this module fully supports 1.063Gbps Fiber Channel protocols, making it a highly reliable and cost-effective solution for upgrading enterprise SANs and NAS storage environments. By admin on 2026-05-10
Q: We use a mix of Cisco Catalyst and Dell switches in our racks. Will this 1.25G SFP module work seamlessly across different brands? By C***t on 2026-01-30

A: Yes! The LS-SM311G-02C is fully SFF-8472 MSA compliant and features broad OEM compatibility. It has been strictly tested by our engineers to work perfectly with Cisco, Dell, Juniper, Arista, and other major switch brands without throwing any protocol errors. By admin on 2026-01-30
Q: We are planning to use these in an outdoor cabinet for a base station backhaul. Does this commercial 0-70°C version work, or do you have an industrial wide-temperature option? By J***n on 2025-12-29

A: For outdoor cabinets, we highly recommend our industrial version, the LS-SM311G-02I, which supports extreme temperatures from -40°C to 85°C. This commercial LS-SM311G-02C model (0 to 70°C) is specifically designed for indoor data centers, campus LANs, and enterprise server rooms. By admin on 2025-12-29
Q: To reach the maximum 2km transmission distance, what exact type of fiber optic patch cables should we purchase? By M***s on 2025-10-19

A: To achieve the full 2km link safely, you need standard Single-Mode Fiber (SMF) with Duplex LC connectors. Ensure your patch cables match the 1310nm wavelength and 9/125µm core size for optimal Tx/Rx optical power performance. By admin on 2025-10-19

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M***g

Chile

Verified Purchase

5 .0

2026-04-24

Upgraded our storage area networks with this 1.063Gbps Fiber Channel transceiver. Rock solid!

156 Helpful vote Comments

R***n

Russian Federation

Verified Purchase

5 .0

2026-04-13

Solid 1.25Gbps link over single-mode fiber.

256 Helpful vote Comments

R***l

Panama

Verified Purchase

5 .0

2026-03-28

Used for a base station backhaul link. The 0 to 70°C range handles well.

231 Helpful vote Comments

S***l

Ireland

Verified Purchase

5 .0

2026-01-26

Works flawlessly with my Juniper gear. 1.25G SFP module compatibility is strictly promised.

134 Helpful vote Comments

M***g

United Kingdom

Verified Purchase

5 .0

2026-01-07

These duplex LC transceivers saved our budget. Great value for datacenter batch deployments!

85 Helpful vote Comments

M***z

Chile

Verified Purchase

5 .0

2025-12-10

Tested the 1310nm Tx/Rx on Arista and Dell. Multibrand OEM compatibility is perfect!

150 Helpful vote Comments

R***g

Bolivia

Verified Purchase

5 .0

2025-09-21

Great Cisco compatible SFP for homelab setups.

239 Helpful vote Comments

R***s

Saudi Arabia

Verified Purchase

5 .0

2025-08-15

Cost-effective gigabit fiber solution for batch deployments.

130 Helpful vote Comments

K***s

Poland

Verified Purchase

5 .0

2025-07-15

Very nice sales to speak to and knowledgeable on the products they sell!

95 Helpful vote Comments

M***e

Spain

Verified Purchase

5 .0

2025-06-21

Super customer experience in terms of Fast delivery. Delivered as promised.

16 Helpful vote Comments

J***k

France

Verified Purchase

5 .0

2025-05-15

Perfect duplex LC fit for Netgear switches.

79 Helpful vote Comments

I***v

United Kingdom

Verified Purchase

5 .0

2025-04-30

my customer is very happy with these 10/25/40G Transceiver Modules\'s and they cost him a fraction of the price of Pulse\'s 10/25/40G Transceiver Modules

65 Helpful vote Comments

D***z

Russian Federation

Verified Purchase

5 .0

2025-04-24

Fast Tx/Rx speeds. Will definitely buy again!

146 Helpful vote Comments

D***k

Ukraine

Verified Purchase

5 .0

2025-04-22

Nice operating temp stability at 70°C.

64 Helpful vote Comments

A***t

Bolivia

Verified Purchase

5 .0

2025-04-17

SFF-8472 MSA compliant, works exactly as described.

134 Helpful vote Comments

P***e

Japan

Verified Purchase

5 .0

2025-03-29

Deployed these for a campus fiber network using single-mode fiber. The 1310nm FP laser transmitter provides excellent signal integrity near the 2km limit. Way better than generic OEM module alternatives!

124 Helpful vote Comments

C***a

Ireland

Verified Purchase

5 .0

2025-02-27

These Optical Transceiver Modules worked as advertised.

55 Helpful vote Comments

J***z

United States

Verified Purchase

5 .0

2025-02-13

Usually next day delivery and all my orders been correct. Also the Optical Transceiver Module are protected nicely in individual bags. Prices are also very competitive and the wide choices are an added bonus.

84 Helpful vote Comments

D***z

Singapore

Verified Purchase

5 .0

2024-11-25

through the I2C interface. Completely transparent to Cisco switches.

210 Helpful vote Comments

M***s

Ecuador

Verified Purchase

5 .0

2024-10-12

Plug and play 2km SMF LC transceiver!

124 Helpful vote Comments

R***S

Spain

Verified Purchase

5 .0

2024-09-21

really great services

76 Helpful vote Comments

B***k

Philippines

Verified Purchase

5 .0

2024-09-04

Satisfied with the Sfp Cage! Great service and good quality!

49 Helpful vote Comments

S***o

Netherlands

Verified Purchase

5 .0

2024-04-26

Very happy with everything! I will come again.

48 Helpful vote Comments

L***n

Russian Federation

Verified Purchase

5 .0

2024-02-28

Competitive pricing. Fast, easy, efficient and secure online shopping

71 Helpful vote Comments

V***e

Hungary

Verified Purchase

5 .0

2024-02-06

Good quality and a true plug and play experience!

124 Helpful vote Comments

V***i

Lithuania

Verified Purchase

5 .0

2024-01-16

The transaction and delivery went very Fast and precise.

54 Helpful vote Comments

R***e

Russian Federation

Verified Purchase

5 .0

2023-12-18

Supper Price Fast shipping Thank you

75 Helpful vote Comments

V***d

United States

Verified Purchase

5 .0

2023-11-18

Very high quality. I ordered several of them and had no problems with any of them

106 Helpful vote Comments

J***n

Japan

Verified Purchase

5 .0

2023-11-06

Thank you for the great products and support.

10 Helpful vote Comments

J***M

New Zealand

Verified Purchase

5 .0

2023-10-24

I have bought many types of Sfp Cage from FS.COM, both of them are compatible with my equipment.

49 Helpful vote Comments

Y***g

Belarus

Verified Purchase

5 .0

2023-09-25

Workable!! We purchased from LINK-PP mainly due to the competitive price if compared to others. We will look for next purchase for our own support team and for our customers.

13 Helpful vote Comments

B***g

Brunei Darussalam

Verified Purchase

5 .0

2023-07-29

Easy to purchase from and received ordered product quickly.

50 Helpful vote Comments

S***r

Maldives

Verified Purchase

5 .0