Overview of QSFP28 LR4 Optical Transceiver

Updated on Dec 18, 2021 by

100G qsfp28 transceiver

There is no denying that 100G data center optics market is accelerating which leads to the great demands for 100G optical transceivers. Among those various 100G modules, the 100G QSFP28 optical transceiver is the most preferred module for smaller size and lower power consumption. In the previous post, the QSFP28 SR4 transceiver has been described in detail. Here, we are going to introduce the QSFP28 LR4 optical transceiver module through the perspectives of definition, working principle, specifications, applications, and FAQs.

QSFP28 LR4: Definition

The QSFP28 LR4 is a hot-pluggable, four-channel, and full-duplex optical transceiver module designed for long-distance transmission up to 10km in the 100G Ethernet network with a working bandwidth of 1295nm to 1310nm. It provides an ideal solution for the super-large-scale data centers for the ever-lasting requirements for transmission distance. Simultaneously, the QSFP 100G LR4 modules are fully compliant with IEEE 802.3ba standard.

How Does QSFP28 LR4 Work?

The 100G QSFP28 LR4 optical module converts four 25Gbps electrical signals into four LAN WDM optical signals and then multiplexes them into a single channel for 100G optical transmission. At the receiving end, the module reuses 100G light input demultiplexing into four LAN WDM optical signals and then converts them into four electrical channel signal output channels.

Figure 1: QSFP28 LR4 Module Working Principle

FS QSFP28 LR4 Solution

All of FS QSFP28 LR4 optical transceiver modules are manufactured to satisfy the industry standard and have been recognized by numerous customers. They are proved to be compatible with over 200 vendors, such as Cisco, Juniper, Arista, Brocade, Dell and so on. Also, they are fully compliant with the QSFP28 MSA, IEEE 802.3ba 100GBASE-LR4 and IEEE 802.3bm CAUI-4 standard.

QSFP 100G LR4: Specifications

Form Type QSFP28
Wavelength 1310nm*
Connector LC Duplex
Cable Type SMF
Max Data Rate 103.125Gbps (4x 25.78Gbps)
Max Cable Distance 10km
TX Power -4.3~4.5dBm
Receiver Sensitivity <-10.6dBm
Transmitter Type 4 x LAN WDM DML (DFB)
DDM/DOM Supported
Commercial Temperature Range 0℃ to 70℃ (32 to 158°F)
Protocols IEEE 802.3ba 100GBASE-LR4, IEEE 802.3bm, QSFP28 MSA, SFF-8665, SFF-8636

*Range: L0 1295.56nm(1294.53-1296.59nm); L1 1300.05nm(1299.02-1301.09nm); L2 1304.58nm(1303.54-1305.63nm); L3 1309.14nm(1308.09-1310.09nm)

QSFP 100G LR4: Benefits

1. All FS QSFP 100G LR4 transceivers must run through programming and an extensive series of platform diagnostic tests to ensure its performance and compatibility. And FS 100GBASE-LR4 optical modules are fully interoperable with non-FS 100G LR4 transceivers as long as they meet the associated industry standard specifications.

2. All QSFP 100G LR4 modules from FS are provided with 30-day exchange service and a five-year warranty policy.

3. FS QSFP 100G LR4 modules can be reconfigured for any network hardware at a moment’s notice with the help of the transceiver coding tool - FS Box. In this way, the QSFP28 LR4 modules are programmed on-site to be compatible with over 200 OEM devices efficiently and flexibly.

4. With large stock in our US, AU, GE, SG, RU, and Asia warehouse, QSFP28 LR4 100G modules can be shipped the same day after ordering.

QSFP 100G LR4: Cabling and Connectivity

Enterprises and data centers are outgoing 10Gb/s and 40Gb/s networks for 100Gb/s connectivity. The QSFP 100G LR4 is in most cases the perfect fit for long-distance 100G direct connection and interconnection.

100G to 100G Direct Connection

The method to get a direct 100G connection doesn’t differ too much from that of 10G/40G. Just plug two 100G QSFP28 LR4 modules into the corresponding ports on the switches, then connect them with LC fiber optic cables.

Figure 2: QSFP28 LR4 Module 100G-100G Direct Connection

100G-100G Interconnect Cabling Solution with Rack Mount Fiber Enclosure

As the following diagram shows, high-density QSFP 100G LR4 interconnect cabling can be achieved by using rack mount fiber enclosure, MTP fiber adapter panels and MTP trunk cable. In this solution, fiber enclosures and adapter panels are used for structured cable management.

Figure 3: QSFP28 LR4 Module 100G-100G Interconnection


Q1: Will the QSFP 100G LR4 work if connected to a CFP 100G LR4 on the other end?

A: Yes, the QSFP 100G LR4 and CFP 100G LR4 modules are featured with same 100G transmission rate and are working on the same wavelength (1310nm), so the QSFP 100G LR4 will work if connected to a CFP 100G LR4 module.

Q2: Is it necessary to clean a transceiver's optical connector? How to clean the QSFP28 LR4 100G transceiver?

A: Dust and contamination can accumulate on transceiver's connectors and cause problems such as reducing the optic launch power. To ensure better connection, FS strongly recommends cleaning both connectors each time you disconnect and reconnect them. FS high-quality One-Push Fiber Optic Pen Cleaner for 1.25mm LC/MU connector is the best cleaning choice for 100GBASE LR4 QSFP28 modules.

Q3: Will using the compatible QSFP 100G LR4 optics in my equipment negatively affect my manufacturer’s warranty?

A: No. Network equipment manufacturers do not require that you use only name-brand optics. In fact, when a product fault or defect occurs in the network, and the fault or defect is not attributable to the use of third-party optics, they will continue to provide support for the affected product under warranty or covered by their support program.

Q4: If I order the QSFP 100G LR4 module, will it work on the 1310 channel of your 18 Channels 1270-1610nm CWDM Mux Demux or will the MUX require a separate 1310 channel?

A: Kindly noted that this 100G QSFP LR4 1310nm module will not work on the 1310 channel of 18 Channels 1270-1610 CWDM Mux Demux, the Mux requires a separate 1310 channel. If you choose the 1310 channel, then the following wavelength that can’t be used: 1270/1290/1310/1330/1350/1370nm.

Q5: Do FS QSFP28 100G LR4 modules support customized service?

A: Yes, all of FS QSFP28 100G LR4 transceivers are provided with customized service. All you need to do is to provide your compatible brands and model type for us. And we appreciate any inquiry for customized products and solutions for your specific preference and requirements.

Related Information

100G QSFP28 Optical Transceiver Comparison

You might be interested in

See profile for Sheldon.
Decoding OLT, ONU, ONT, and ODN in PON Network
Mar 14, 2023
See profile for Irving.
What's the Difference? Hub vs Switch vs Router
Dec 17, 2021
See profile for Sheldon.
What Is SFP Port of Gigabit Switch?
Jan 6, 2023
See profile for Migelle.
PoE vs PoE+ vs PoE++ Switch: How to Choose?
May 30, 2024
See profile for Moris.
How Much Do You Know About Power Cord Types?
Sep 29, 2021