100G QSFP28 SR4 Vs. 100G QSFP28 IR4

Among all the 100G transceivers, most Ethernet users intended to use 100G QSFP28 transceivers instead of other 100G transceivers to connect switches, routers and servers. There are several common types of 100G QSFP28 modules, including 100G QSFP28 LR4,100G QSFP28 SR4, 100G CWDM4 and 100G PSM4. LR4, SR4 and IR4 are three common types of 100G QSFP28 modules. It is known to all that LR is set for long-reach transmission while SR for short-reach transmission. How about IR4? What is the difference between IR4 and SR4? A satisfied answer will be provided in this article.

Introduction to 100G QSFP28 SR4

100G QSFP28 SR4 is a pluggable and parallel fiber optic transceiver for 100G Ethernet. This transceiver is a high performance module for short-range multi-lane data communication and interconnect applications. It offers 4 independent transmit and receive channels, each capable of 25Gbps operation in each direction with 112.2Gbps bandwidth for an aggregate data rate of 100Gbps with each lane operates at 28.05Gbps. 100G QSFP28 SR4 is designed to operate over multimode fiber systems using a nominal wavelength of 850 nm. The transmission distance can be up to 70 m using OM3 fiber or 100 m using OM4 fiber. And this optical transceiver interfaces 12-fiber MTP/MPO connectors. QSFP-100G-SR4 supports 100GBASE-SR4 Ethernet Links, Infiniband QDR and DDR links, Client-side 100G Telecom links and many other optical links.

Overview on 100G QSFP28 IR4

According to the QSFP28 Multi-Source Agreement (MSA), 100G QSFP28 IR4 is designed with form factor, optical/electrical connection and digital diagnostic interface. It is compliant to the QSFP28 MSA and IEEE 802.3bm 100GBASE PSM4. 100G QSFP28 IR4 works over single-mode fiber with a maximum transmission distance of 2 km. This 100G QSFP28 full-duplex optical module offers 4×25 Gbps for an aggregate data rate of 100Gbps. It interfaces an MTP/MPO connector. Nowadays, vendors like FS.COM prefer to use IR4 as the model No. but still describe it as CWDM4 in the product description title. 100G QSFP28 IR4 supports 100GBASE-IR4 links, Infiniband QDR and DDR links, Data center and Enterprise networking...

The unique design of this high performance module: a 2-wire serial interface is available to send and receive more complex control signals and to receive digital diagnostic information. Individual channels can be addressed and unused channels can be shut down for maximum design flexibility. It has been designed to meet the harshest external operating conditions including temperature, humidity and EMI interface.

100G QSFP28 SR4 Vs. 100G QSFP28 IR4

• Wavelength—100G QSFP28 IR4 uses longer wavelength than 100G QSFP28 SR4. For they are 1310 nm and 850 nm respectively.
• Transmission distance—The maximum transmission distance of 100G QSFP28 IR4 is 2 km and 100G QSFP28 SR4 is 100 m. So 100G QSFP28 IR4 is much longer than 100G QSFP28 SR4 on transmission distance due to 100G QSFP28 IR4 works on single-mode fiber to transmit while the media type of 100G QSFP28 SR4 is multimode fiber.
• Technology support—100G QSFP28 IR4 is built-in Digital Diagnostic Monitoring functions which can monitor the module’s temperature, receiver power, transmitter bias current, and transmitter power. 100G QSFP28 SR4 has not this technique support but it is equipped with VCSEL transmitter.
• Cost—100G QSFP28 IR4 costs a lot compared to 100G QSFP28 SR4. At FS.COM, QSFP28 100G CWDM4 is $1350 while 100G QSFP28 SR4 is $269. The price is quintuple. You may astonished at this price disparity. This is because there is a big slump in 100G QSFP28 SR4 and 40G QSFP28 SR4 transceivers at FS.COM recently. So buying it now is really a good deal for cost of the similar products is much higher on other online shops, such as Amazon, 100G QSFP28 SR4 costs $842.

Summary

Through this passage, we figure out that the differences between 100G QSFP28 SR4 and 100G QSFP28 IR4 lie in wavelength, transmission, technology support and cost. Different types differ in function. If you are looking for 100G transceiver to transfer data over short range, and then 100G QSFP28 SR4 module is ideal with maximum transmission distance of 100 m. When the long transmission distance is considered, QSFP28 100G CWDM4 or QSFP28 100G PSM4 is highly recommended for their maximum transmission distance is 2 km and 500 m respectively.