TP-Link TL-SM311LS Gigabit Single-Mode SFP Module Price in Kenya

The TP-Link TL-SM311LS is a Gigabit single-mode SFP transceiver designed for long-distance fibre connections between compatible switches, media converters and other networking equipment.

Current TP-Link versions of the SM311LS support 1.25Gbps transmission, 1310nm wavelength, 9/125µm single-mode fibre, LC duplex connectivity and distances up to 20 kilometres. They also support Digital Diagnostic Monitoring (DDM), SFP-MSA compatibility and hot-swappable installation. 

Older TL-SM311LS revisions were rated for up to 10km, so the exact hardware revision should be checked before installation. 

TP-Link TL-SM311LS Specifications

TP-Link's current Omada documentation confirms 20km reach, 1310nm wavelength, 1.25Gbps rate, LC duplex interface, DDM, SFP-MSA and hot-swappable operation. 

What Is the TP-Link TL-SM311LS?

The TL-SM311LS is an optical transceiver that plugs into a compatible Gigabit SFP port.

It converts electrical Ethernet signals from the switch or media converter into optical signals for transmission through single-mode fibre.

A typical connection is:

Switch A → TL-SM311LS → Single-Mode Fibre → TL-SM311LS → Switch B

This allows network equipment separated by several kilometres to communicate over fibre without needing Ethernet repeaters along the route.

1000BASE-LX Single-Mode SFP

Current TP-Link documentation identifies the SM311LS as an Omada 1000Base-LX SMF Mini GBIC Module. 

It is designed for Gigabit Ethernet applications requiring much greater transmission distance than a short-range 850nm multimode SFP.

Typical characteristics include:

• 1Gbps Ethernet

• 1.25Gbps optical data rate

• 1310nm wavelength

• Single-mode fibre

• LC duplex connector

• Up to 20km transmission

1.25Gbps Data Rate

The TL-SM311LS operates at:

1.25Gbps

This supports standard Gigabit Ethernet transmission.

TP-Link specifies the module's data rate as 1.25Gbps on current and earlier versions. 

1310nm Wavelength

The module operates at:

1310nm

This wavelength is widely used for Gigabit Ethernet transmission over single-mode fibre.

Both sides of a conventional TL-SM311LS link typically use the same type of module and communicate over a duplex fibre connection.

Single-Mode Fibre Support

The TL-SM311LS is designed for:

9/125µm Single-Mode Fibre

This makes it substantially more suitable for long-distance links than the multimode TL-SM311LM.

TP-Link specifically lists 9/125µm SMF as the required fibre type. 

Maximum Transmission Distance

Current TP-Link SM311LS versions support distances of up to:

20 kilometres

over suitable 9/125µm single-mode fibre. 

However, older hardware versions were specified for:

10 kilometres

which means the exact module revision matters.

TL-SM311LS Reach by Version

For a new deployment, check the label and datasheet of the actual supplied module rather than assuming every TL-SM311LS has the same reach.

LC Duplex Connector

Current SM311LS modules use an:

LC Duplex optical interface

The connection normally requires two fibre strands:

TX → Fibre Strand 1

RX ← Fibre Strand 2

TP-Link specifies LC Duplex on its current SM311LS models. 

Some earlier regional documentation identifies the connector as LC/UPC, which is consistent with the conventional polished LC interface used by the module. 

Is the TL-SM311LS BiDi?

No.

The TL-SM311LS is a conventional duplex SFP rather than a single-fibre BiDi transceiver.

This means a standard installation normally uses:

Two fibre strands

and an:

LC-LC Duplex Single-Mode Patch Cord

If only one fibre strand is available, a matched BiDi SFP pair would normally be more appropriate.

Digital Diagnostic Monitoring – DDM

Current TL-SM311LS versions support:

DDM – Digital Diagnostic Monitoring

DDM can allow compatible switches to monitor operating parameters from the SFP.

Depending on the switch, this may include:

• Optical transmit power

• Optical receive power

• Module temperature

• Supply voltage

• Laser bias

• Diagnostic alarms

TP-Link lists DDM as a standard hardware feature on current SM311LS versions. 

SFP-MSA Compatibility

The SM311LS supports the Small Form-factor Pluggable Multi-Source Agreement, or SFP-MSA. 

This defines key mechanical and electrical characteristics of the SFP form factor.

However, SFP-MSA compliance does not guarantee that every manufacturer's switch will accept every third-party transceiver. Vendor compatibility should still be checked.

Hot-Swappable SFP Design

The TL-SM311LS is designed to be:

Hot-swappable

This allows compatible modules to be inserted and removed from supported SFP cages without replacing the entire network device.

TP-Link lists hot-swappable operation on current versions. 

Watch TP-Link TL-SM311LS Video

https://youtu.be/pHTFNOi3jvA

The TP-Link TL-SM311LS is designed for situations where standard copper Ethernet or short-range multimode fibre cannot cover the required distance. By using 1310nm optics over single-mode fibre, current versions can extend a Gigabit Ethernet connection to approximately 20km.

This makes it particularly useful for connecting buildings, network cabinets, remote offices, CCTV sites, ISP distribution points and campus facilities. The link remains point-to-point Ethernet, with one compatible module normally installed at each end.

The current module's DDM functionality can also make fibre troubleshooting easier because technicians may be able to inspect transmit and receive optical power directly from compatible managed networking equipment. 

TP-Link TL-SM311LS for TP-Link Switches

TP-Link designed the TL-SM311LS for compatible TP-Link switches equipped with Gigabit SFP ports.

Current documentation lists compatibility with TP-Link switches with Gigabit SFP slots, while older documentation specifically mentions JetStream switches. 

Typical applications include:

• Core-to-access switch links

• Building uplinks

• Remote cabinet connections

• Campus backbone links

• Fibre distribution networks

TP-Link TL-SM311LS with JetStream Switches

The TL-SM311LS is suitable for compatible TP-Link JetStream managed and smart switches.

A typical configuration is:

JetStream Switch → TL-SM311LS → OS2 Fibre → TL-SM311LS → Remote JetStream Switch

TP-Link recommends using the same transceiver model at both ends for reliable connectivity.

TP-Link TL-SM311LS with MC220L

TP-Link identifies the MC220L Gigabit Media Converter as compatible with the TL-SM311LS. 

A typical configuration is:

RJ45 Ethernet → MC220L → TL-SM311LS → Single-Mode Fibre → Remote SFP Device

This is useful when one side of the network does not already have a built-in optical interface.

TL-SM311LS with MC210CS

TP-Link also states that the module can work with MC210CS using a single-mode fibre connection. 

Compatibility should still be checked for the exact media converter and network configuration.

TP-Link TL-SM311LS for Building-to-Building Connections

The TL-SM311LS is well suited to connecting separate buildings.

A fibre link provides several advantages compared with copper:

• Much greater distance

• Electrical isolation

• Immunity to electromagnetic interference

• Gigabit bandwidth

• Reduced lightning-related electrical conduction between network devices

Current 20km-rated versions can cover distances far beyond typical campus or compound links. 

TP-Link TL-SM311LS for ISP Networks

ISPs can use the module for point-to-point Gigabit Ethernet connections such as:

• POP-to-POP links

• Tower uplinks

• Distribution switches

• Customer enterprise links

• Remote office links

• Access network connections

For larger backbone requirements, a 10G SFP+ solution may be more appropriate.

TP-Link TL-SM311LS for CCTV Networks

Example:

IP Cameras → PoE Switch → TL-SM311LS → Single-Mode Fibre → TL-SM311LS → Core Switch → NVR

This is useful for large installations where cameras and switches are distributed across a wide compound.

TP-Link TL-SM311LS for Campus Networks

Suitable installations include:

• Schools

• Universities

• Hospitals

• Hotels

• Industrial sites

• Government compounds

• Office parks

• Warehouses

Single-mode fibre allows network designers to extend Gigabit connectivity between distant buildings without being constrained by the 100m limit of conventional copper Ethernet.

TP-Link TL-SM311LS vs TL-SM311LM

The most important difference is the fibre type and reach.

TP-Link's own documentation lists 1310nm single-mode operation for the LS and 850nm multimode operation for the LM. 

TL-SM311LS vs 20KM Generic SFP

Both may provide 1Gbps connectivity over single-mode fibre, but the key difference is compatibility and manufacturer support.

The TP-Link module provides:

• TP-Link product compatibility

• Manufacturer specifications

• DDM support on current versions

• SFP-MSA support

• Defined operating temperature

• TP-Link warranty channel depending supplier

A generic module may offer similar optical performance but should be checked carefully for switch compatibility.

TL-SM311LS vs 1G BiDi SFP

TL-SM311LS vs 10G SFP+

The TL-SM311LS should not be treated as a 10Gbps transceiver.

20KM vs 10KM TL-SM311LS Versions

TP-Link has released several hardware revisions.

This is important because older TL-SM311LS versions are documented for 10km, while newer versions are documented for 20km.

Therefore, product listings that appear inconsistent may actually refer to different hardware revisions.

Before ordering for a route longer than 10km, verify:

Model revision + maximum reach printed on the datasheet or packaging.

Operating Temperature

Current versions are rated for an operating temperature of:

0°C to 70°C

and operating humidity of:

10% to 90% RH non-condensing. 

This is a commercial-temperature module rather than an industrial-temperature SFP.

TL-SM311LS Dimensions

Current TP-Link versions measure approximately:

55.4 × 14.6 × 12.9mm. 

The compact SFP form factor allows high port density on compatible switches.

Fibre Loss and 20KM Reach

The 20km specification should not be interpreted as a guarantee that every 20km physical route will work regardless of fibre condition.

Actual performance depends on:

• Fibre attenuation

• Connector loss

• Number of splices

• Patch-panel loss

• Fibre bends

• Connector cleanliness

• Optical power budget

• Engineering margin

For long fibre routes, testing should be completed before commissioning.

Testing a TL-SM311LS Fibre Link

Optical Power Meter

An Optical Power Meter can measure the optical signal arriving at the remote end.

This is useful when the SFP does not establish a link.

OTDR

An OTDR can help identify:

• Fibre length

• Splice losses

• Connector events

• Excessive attenuation

• Fibre breaks

• Macrobends

VFL

A Visual Fault Locator can help with basic continuity testing and identification of visible faults over shorter fibre sections.

Cleaning LC Connectors

Before installing the SFP, LC connectors should be properly cleaned.

Contamination can cause:

• Increased attenuation

• Intermittent links

• Low Rx power

• Packet errors

• Link failure

Long-distance links are particularly sensitive to unnecessary optical loss.

TP-Link TL-SM311LS Price in Kenya

Current Kenyan listings show the TL-SM311LS at several price points.

Senetic Kenya currently lists:

TL-SM311LS 20KM: approximately KES 2,350 net / KES 2,726 gross. 

Jumia Kenya currently lists the SM311LS at approximately:

KES 2,690. 

Jiji also shows a current listing around:

KES 2,060.

Approximate TP-Link TL-SM311LS Prices in Kenya

These are third-party market examples and can change with stock, VAT, hardware revision and supplier.

Contact Fiber Optics Kenya for the current TL-SM311LS price and availability.

What Affects TL-SM311LS Price in Kenya?

Pricing can vary according to:

• Hardware revision

• 10km or 20km version

• Supplier

• Warranty

• VAT

• Stock availability

• Quantity ordered

• Distributor source

The model revision should therefore be compared alongside price.

How to Choose the Correct TL-SM311LS

Before buying, verify:

1. The switch has a compatible 1G SFP port.

2. The installed cable is single-mode fibre.

3. The fibre uses the appropriate LC termination at the SFP side.

4. Two fibre strands are available for duplex operation.

5. The route is within the module's rated distance.

6. The exact hardware revision provides the required reach.

7. The device supports the module.

8. DDM is supported if optical monitoring is required.

Recommended Accessories

Frequently Asked Questions About TP-Link TL-SM311LS

What is the TP-Link TL-SM311LS?

It is a Gigabit single-mode fibre SFP transceiver.

What speed does TL-SM311LS support?

It supports Gigabit Ethernet with a 1.25Gbps optical data rate. 

What wavelength does it use?

1310nm. 

Is TL-SM311LS single mode?

Yes.

What fibre size does it use?

9/125µm single-mode fibre. 

What is its maximum distance?

Current versions support up to 20km. 

Why do some TL-SM311LS listings say 10km?

Older hardware versions were specified for up to 10km. 

Should I check the hardware revision?

Yes, especially for links longer than 10km.

What connector does it use?

LC Duplex on current versions.

Is it LC/UPC?

Earlier regional TP-Link specifications identify LC/UPC, while newer documentation specifies LC Duplex. 

Does it require two fibre cores?

Yes, under normal duplex operation.

Is TL-SM311LS a BiDi SFP?

No.

Can it work using one fibre strand?

Not in the conventional TL-SM311LS duplex configuration.

What should I use if I only have one fibre core?

A compatible matched BiDi SFP pair may be more suitable.

Does TL-SM311LS support DDM?

Current versions do.

What does DDM mean?

Digital Diagnostic Monitoring.

Is TL-SM311LS hot-swappable?

Yes. 

Is it SFP-MSA compatible?

Yes. 

What voltage does it use?

3.3V. 

Can it work with TP-Link switches?

Yes, with compatible Gigabit SFP-equipped TP-Link switches. 

Can it work with JetStream switches?

Yes, compatible JetStream SFP ports are supported. 

Can it work with MC220L?

Yes. TP-Link lists the MC220L as compatible. 

Can it work with MC210CS?

TP-Link states that it can work with MC210CS over single-mode fibre. 

Can it connect two switches?

Yes.

Can it connect two buildings?

Yes.

Can it connect buildings several kilometres apart?

Yes, provided the total link loss remains within specification.

Can it work over 15km?

A current 20km-rated version can potentially support such a route, subject to optical loss. Do not use an older 10km version for a 15km design.

Can it work over 20km exactly?

Potentially, but actual fibre losses and engineering margin must be considered.

Can I use it for 40km?

No. Use a suitably rated 40km SFP.

Is it suitable for ISP networks?

Yes, for compatible Gigabit point-to-point fibre links.

Is it suitable for CCTV?

Yes.

Is it suitable for campus networks?

Yes.

Is it suitable for enterprise networks?

Yes.

Is it suitable for FTTH?

It can be used for point-to-point Ethernet links within an FTTH network, but it is not an EPON or GPON OLT/ONU transceiver.

Is TL-SM311LS an EPON SFP?

No.

Is TL-SM311LS a GPON SFP?

No.

Can it replace an EPON PX20 module?

No. They perform different functions.

Can it work with multimode fibre?

It is designed for 9/125µm single-mode fibre. Use the correct multimode SFP where multimode fibre is installed.

What is the difference between TL-SM311LS and TL-SM311LM?

TL-SM311LS uses 1310nm single-mode fibre for long-distance links, while TL-SM311LM uses 850nm multimode fibre for shorter links. 

How far does TL-SM311LM reach?

Up to around 550m on suitable multimode fibre.

How far does current TL-SM311LS reach?

Up to 20km.

Can I connect TL-SM311LS at one end and TL-SM311LM at the other?

No. Their fibre types and wavelengths do not match.

Should I use the same TL-SM311LS module at both ends?

TP-Link recommends using the same transceiver model between switches for reliable connectivity. 

Can I use LC-LC patch cords?

Yes.

Can I use LC-SC patch cords?

Yes, if the opposite termination is SC and the fibre type/polish is compatible.

Should the patch cord be single mode?

Yes.

Should I use simplex or duplex?

Duplex.

Can dirty connectors stop the link?

Yes.

Should I clean LC connectors before installation?

Yes.

Can I test the link with an Optical Power Meter?

Yes.

Can I test the route with an OTDR?

Yes.

What is the operating temperature?

Current TP-Link versions are specified for 0°C to 70°C. 

Is this an industrial-temperature SFP?

No. The standard module is a commercial-temperature product.

What are the dimensions?

Approximately 55.4 × 14.6 × 12.9mm on current versions. 

What is the TP-Link TL-SM311LS price in Kenya?

Current market examples range from about KES 2,060 to KES 2,726, depending on supplier and tax treatment. 

How much is TL-SM311LS on Jumia Kenya?

A current listing is approximately KES 2,690. 

Do you supply TL-SM311LS modules?

Yes, subject to stock availability.

Do you supply TL-SM311LM modules?

Yes.

Do you supply 20KM SFP modules?

Yes.

Do you supply 40KM SFP modules?

Yes.

Do you supply BiDi SFP pairs?

Yes.

Do you supply single-mode fibre patch cords?

Yes.

Do you supply media converters?

Yes.

Do you supply OTDRs and Optical Power Meters?

Yes.

Can businesses and ISPs order in bulk?

Yes. Bulk orders are suitable for ISPs, enterprises, CCTV integrators, campuses and fibre contractors.

Do you deliver outside Nairobi?

Yes. Fiber Optics Kenya supplies fibre optic and networking equipment throughout Kenya.

Why Buy TP-Link TL-SM311LS from Fiber Optics Kenya?

Contact Fiber Optics Kenya

Fiber Optics Kenya
Lyric House, 7th Floor Room S9
Kimathi Street, Nairobi

Phone: +254 704 991 492
Email: info@fibreopticskenya.co.ke

The TP-Link TL-SM311LS Gigabit Single-Mode SFP Module is designed for long-distance Gigabit Ethernet connections over single-mode fibre. Current models support 1.25Gbps, 1310nm operation, 9/125µm fibre, LC duplex connectivity, DDM and distances up to 20km. 

It is a strong option for building-to-building fibre, enterprise networks, campus infrastructure, CCTV backbones, ISP distribution links and compatible TP-Link switches or media converters.

Current Kenyan market examples place the TL-SM311LS at roughly KES 2,060–2,726, although prices vary with stock, VAT and hardware revision. 

The most important point when purchasing this model is to check the hardware revision, because older TL-SM311LS versions are rated for 10km while newer versions support up to 20km. 

Contact Fiber Optics Kenya for the current TP-Link TL-SM311LS price in Kenya, TL-SM311LM modules, 20KM and 40KM SFPs, BiDi transceivers, single-mode fibre patch cords, media converters, testing equipment, bulk orders and nationwide delivery.