The market transition to 100G is in full force, fueled primarily by the seemingly insatiable need for networking demand by hyperscale data centers and cloud service. And in the past few years, a number of 100G module form factors and MSAs have emerged. However, the industry has largely aligned behind QSFP28 as the form factor of choice for short 100G links (<10 km). FS.COM complies with this trend and has launched several kinds of 100G QSFP28 optics for sale. And soon we will set up inventory for QSFP28 100GBASE-CWDM4 and QSFP28 100GBASE-PSM4 transceivers.
Both CWDM4 and PSM4 architectures take the 100G signal and carry it over 4 separate channels. In the case of CWDM4, different lambdas define the four channels, while in PSM4, distinct fibers define the channels. CWDM4 uses an optical multiplexer and demultiplexer to transmit the signals up to 2 km with only two fibers. Different from CWDM4, PSM4 uses 8 parallel fibers (4 transmit and 4 receive), each transmitting at 25 Gbps. It can transmit the signal up to 500 m.