A BiDi SFP module is a bidirectional fiber optic transceiver that enables simultaneous transmit and receive over a single strand of single-mode fiber, instead of the traditional two-fiber setup. In practical network deployments, this makes BiDi SFP modules a highly effective solution for. This article will explain the BiDi optical transceiver, analyze its advantages and disadvantages, discuss applicable application scenarios, and introduce the various common types of BiDi transceivers.