15 Nov

Basic Understanding  of 100G QSFP28 Fiber Optic Modules

As data centers around the global continues to explore their options for increase in network speeds and bandwidth constantly. The development of 100G fiber optic transceiver has experienced a lot of challenges and competition among most data centers and network service providers.According to authoritative statistics by 2018, the world will have 38% of service providers to deploy 100G network, which means 100G era has arrived since 40G  could not keep to pace with the modern requirement. if you really want to flourish and remain competitive in business  you must continually improve your network speed to meet people’s growing network needs.100G optical module is an important part of the 100G network, and 100G QSFP28 optical modules is the industry’s most respected 100G optical module, this tutorial will be introduced in detail.

About 100G QSFP28 optical modules

The structural composition of 100G QSFP28 optical module and 40G QSFP + optical module is the same  both are using four Fiber Channel to transmit data, the difference lays in  the transmission rate of 100G QSFP28 optical module fiber channel which can be up to 28Gbps. Mainly for 100G transmission applications Compared to 100G CFP optical modules, the 100G QSFP28 optical module is better suited for high-density cabling and is widely favored by most data centers.

The types of  optical module

100G QSFP28 optical module first appeared in 2013, after several years of development, 100G QSFP28 optical module has been derived from a number of categories, respectively, with different optical module standards and suitable for different transmission applications.

100GBASE-SR4 QSFP28 optical module

According to research 100Gbase-SR4 QSFP28 is the most popular QSFP28 module. most of the multi-mode fiber used in the data centre  are mostly designed to support  multi-mode fiber short-distance transmission application standards.100GBASE-SR4 QSFP28 optical module uses MTP interface (8 Core), the OM3 multi-mode fibre transmission achieves a distance of 70m while OM4 multimode fiber can achieve a transmission distance is 100m, 100G QSFP28 SR4 is a standard published by IEEE.

100GBASE-LR4 QSFP28 optical module

100G QSFp28 LR4 is another 100G standards published by IEEE. It anchors on longer transmission distance over single-mode fibre It can support distances up to 10km. 100GBASE-LR4 QSFP28 optical module also uses four fiber channel; the difference is that it introduces the WDM technology, four different wavelengths of Fiber Channel can be multiplexed onto a fiber for transmission, so 100GBASE-LR4 QSFP28 optical module Is the duplex LC interface.

100GBASE-PSM4 QSFP28 optical module

100GBASE-PSM4 is a multi-source protocol (MSA), mainly for 100G QSFP28 optical module development. 100GBASE-PSM4 QSFP28 optical module is mainly used for long-distance transmission applications, the use of MTP interface (8-core), and single-mode multi-core fiber with the transmission distance can reach 500m.

100GBASE-CWDM4 QSFP28 optical module

100GBASE-CWDM4 is also a multi-source protocol (MSA), 100GBASE-CWDM4 QSFP28 optical module also introduced the WDM technology, the use of duplex LC interface, and single-mode fiber with the transmission distance can reach 2km, its transmission distance is shorter than 100GBASE-LR4 QSFP28 light module and the price is much cheaper.

100G QSFP28 high speed cable

In addition to 100G QSFP28 optical modules, 100G QSFP28 high-speed cable has also been widely welcomed, because this product can greatly reduce the cost of 100G short-distance transmission. There are two types of 100G QSFP28 high-speed cable: QSFP28 to QSFP28 high-speed cable and QSFP28 to SFP28 high-speed cable. QSFP28 to QSFP28 high-speed cable at both ends are QSFP28 fiber optic transceivers; QSFP28 to SFP28 high-speed cable is one end of the QSFP28 fiber transceiver device, the other end is four SFP28 fiber transceivers. In general, 100G QSFP28 high-speed cable length is not more than 5m.

Commonly Asked Questions About QSFP28 Transceiver

Is 100G QSFP28 cost efficient?

100G now delivers a compelling price point, offering far greater capacity increases for the cost. And it still future-proofing the network with unsurpassed bandwidth.

How Many QSFP28 Transceiver Modules Can Be Accommodated In One Switch?

With QSFP28 transceiver, a one rack-unit (RU) switch can accommodate up to 36 QSFP28 ports. While many more varieties of transceivers and cables (DACs and AOCs) can plug into these ports.

What is the maximum power consumption of 100G QSFP transceivers?

This information is increasingly important to determine the system power draw for customers, as the optic power is a high percentage of overall system power.

The table below summarizes the power consumption of Arista 100G QSFP transceivers.

Product Number

Max Power Consumption


QSFP-100G-SR4  3.5W




QSFP-100G-ER4 4W



Advantages of QSFP28

100G QSFp28 enjoys the following  100G networking can be

1. customised


3.easily expanded to allow for changes in the future.

4.speed and capacity


QSFP28 transceiver module have become the universal data centre adoption form for 100G optical transmission. 100G QSFP28 modules are the suggested methods for short distance transmission over multimode.100Gbase-SR4 QSFP28 module is suggested for single-mode applications, 100Gbase-PSM4 supporting 500m, 100Gbase-CWDM4 supporting 2km and 100Gbase-LR4 supporting 10km are available.With higher port density, lower power consumption and lower cost, QSFP28 transceiver is an ideal alternative for large scale data centers, as well as future network expansions.