Brief Introduction to QSFP 100G PSM4 Optical Transceiver

Updated on Jan 5, 2022

100G QSFP28 Transceiver

With the growing data rates of optical interconnects, the 100G optical transceiver is booming now in the data center market. QSFP28 is the main form factor for 100G Ethernet in the data center with the merits of high density and low consumption. In the previous post, we described the QSFP 100G SR4 and QSFP 100G LR4 optical transceivers specifically. Today, we are going to make a brief introduction to the QSFP28 PSM4 optical transceivers through the perspectives of definition, working principle, specifications, applications, and FAQs.



What Is QSFP 100G PSM4?

The 100G QSFP28 PSM4 is a high-speed, hot-pluggable and low-power-dissipation optical transceiver with a built-in digital diagnostics function. Defined by the 100G PSM4 MSA, the QSFP28 PSM4 takes a different transmission approach. Unlike the QSFP28 SR4 module, the QSFP 100G PSM4 transmits on a single-mode fiber with a wavelength of 1310nm and supports link lengths of up to 500 meters with 12 fiber MTP/MPO connectors. The QSFP28 PSM4 module offers four independent transmit and receive channels and each channel operates at 25Gbps, aggregating data rate of 100Gbps.

How Does QSFP 100G PSM4 Work?

The QSFP 100G PSM4 converts parallel electrical input signals into parallel optical signals by the Layser Array and then transmits them in parallel on the MTP/MPO single-mode ribbon fiber. Upon reaching the receiving termination, the PIN array converts the parallel optical signals into parallel electrical signals. The QSFP28 PSM4 module works in much the same way as the QSFP28 SR4 optical transceiver. The difference is that the former operates on single-mode fiber while the latter operates on OM3/OM4 multimode fiber.

Figure 1: QSFP 100G PSM4 Module Working Principle


FS QSFP 100G PSM4 Datasheet

All of FS QSFP 100G PSM4 optical transceivers are manufactured to satisfy the industry standard and have been recognized by numerous customers. They are proven to be compatible with over 200 vendors, such as Cisco, Juniper, Arista, Brocade, Dell, and so on.

QSFP28 PSM4 Specification

Form Factor QSFP28
Wavelength 1310nm
Connector MTP/MPO-12
Cable Type SMF
TX Power -9.4~2dBm
Protocols QSFP28 MSA Compliant
Max Data Rate 103.125Gbps (4x 25.78Gbps)
Max Cable Distance 500m
Transmitter Type 4x DFB
Receiver Type PIN
DDM/DOM Supported
Receiver Sensitivity <-12.66dBm
Commercial Temperature Range 0° to 70° (32 to 158°F)
CDR (Clock and Data Recovery) TX & RX Built-in CDR

QSFP28 PSM4 Benefits

1. All FS QSFP28 PSM4 modules must run through programming and an extensive series of platform diagnostic tests to ensure their performance and compatibility. And FS 100GBASE-PSM4 optical modules are fully interoperable with non-FS 100G PSM4 transceivers as long as they meet the associated industry standard specifications.

2. All QSFP28 PSM4 transceivers from FS are provided with exchange service within 30 days and a five-year warranty policy.

3. FS 100G QSFP28 PSM4 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 PSM4 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, UK, and Asia warehouses, QSFP28 PSM4 100G modules can be shipped the same day after ordering.

QSFP 100G PSM4 Cabling and Connectivity

The QSFP 100G PSM4 is the best choice of low-cost scheme capable of transmitting less than 500m. On one hand, it can be used for 100G to 100G direct connection. On the other hand, the QSFP28 PSM4 transceiver can also be applied to achieve 25G to 100G migration in a short distance.

100G to 100G Direct Connection

To get a direct 100G connection, just plug two QSFP 100G PSM4 optical transceivers into the corresponding ports on the 100G switches, and connect them with single-mode MTP cables.

Figure 2: QSFP 100G PSM4 Module 100G to 100G Direct Connection

25G to 100G Migration

How to migrate your network from 25G to 100G? The method to get the 25G to 100G migration is a very simple option. FS offers a gradual migration with the support of the 100G QSFP28 PSM4 modules and four 25G SFP28 LR transceivers, which are connected by the MTP to LC OS2 single mode fiber cables.

Figure 3: QSFP 100G PSM4 25G to 100G Migration


Q1: What is 100G PSM4 standard? Do the FS QSFP 100G PSM4 modules comply with it?

A: The 100G PSM4 standard is a multi-source protocol (MSA) designed to deliver a low-cost solution that delivers four 25Gbps wavelengths over a single mode fiber in addition to the IEEE 100G Ethernet specification, specifically designing for transmission distances of 500m of the network applications. All FS QSFP28 PSM4 modules are fully compliant with QSFP28 MSA and IEEE 802.3bm 100GBASE PSM4 standard.

Q2: Can the QSFP 100G PSM4 optics be used to deliver 4x25G over single-mode fiber using a breakout cable and connect to 4x25GBASE LR SFP28 modules?

A: Yes, this kind of connection is feasible, the QSFP28 PSM4 optics can be used to deliver 4x 25G over single-mode fiber using a breakout cable and connect to 4x 25GBASE LR SFP28 modules.

Q3: What’s the meaning that the QSFP 100G PSM4 vendor name is written under compatible? Do you check the compatibility of QSFP28 PSM4 transceivers?

A: The QSFP 100G PSM4 vendor name written under compatible means that each different brand corresponds to a compatible module. FS will check the compatibility of every QSFP28 PSM4 module and the corresponding brand model. FS Test Assured Program provides real machine detection module compatibility to ensure compatibility.

Q4: Is any necessary to clean the QSFP28 PSM4 module’s optical connector?

A: It is highly recommended that a data center facility implement cleaning procedures for all fiber optic connectors to reduce link failures and unnecessary replacement of expensive and critical network equipment.

Q5: Will using compatible QSFP 100G PSM4 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.


Related Information

100G QSFP28 Optical Transceiver Comparison

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