The following table shows a summary of comparison between 100G PSM4 and CWDM4 QSFP28 transceivers:
| 100G PSM4 QSFP28 | 100G CWDM4 QSFP28 | |
| Optical Transmitter | Four integrated sillicon photonic modulators and one distributed-feedback laser | Four CWDM directly-modulated lasers |
| Four-wavelength CWDM Multiplexer | No Needed | Needed |
| Connector | MPO connector with eight fibers | Duplex LC connector |
| Fiber | Parallel Ribbon SMF (8 Fibers) | Duplex SMF |
| Reach | 500 meters | 2 kilometers |
