With the growing demands for data transmission rate, the market of 100G optical module is also expanding rapidly. IEEE organization was designed two optical module standards for 100G network: 100G SR4 QSFP28 and 100G LR4 QSFP28. However, in practical application, due to the diversity of optical fiber link, these two standards are far from meeting the needs of deploying data centers in a cost-effective way. And thus CWDM4 MSA and 100G CLR4 league are also proposed 100G CWDM4 QSFP28 standard and 100G CLR4 QSFP28 standard which the transmission distance reaches 2km. Here the article will introduce 100G QSFP28 Transceiver that complied with these two standards.

100G CWDM4 QSFP28 optical module

100G CWDM4 QSFP28 is the standard announced by CWDM4 MSA in 2014, it is 100G transmission mode based on single-mode coarse wavelength division multiplexing (CWDM) technology. 100G CWDM4 QSFP28 optical module that complied with this standard adopts duplex LC interface, and using four central wavelength (1271nm, 1291nm, 1311nm and 1331nm) to transmit optical signal.  It is worthy note that 100G CWDM4 QSFP28 optical module need to be used in optical fiber link which has forward error correction (FEC) function to ensure the stability of optical fiber transmission system.

Wavelength	Central Wavelength	Range of Wavelength
Lane 1	1271 nm	1264.5 to 1277.5 nm	Tx0, Rx0
Lane 2	1291 nm	1284.5 to 1297.5 nm	Tx1, Rx1
Lane 3	1311 nm	1304.5 to 1317.5 nm	Tx2, Rx2
Lane 4	1331 nm	1324.5 to 1337.5 nm	Tx3, Rx3