Each transceiver module comes with a vendor-defined operating temperature range. exceed or beyond the normal temperature range, then the modules will fail to perform well or even won't operate normally. Selecting the appropriate temperature grade ensures that your network infrastructure operates optimally under varying environmental. The performance and lifetime of optical modules directly affect the stability and transmission efficiency of the network, while the operating temperature is one of the important factors affecting the performance and lifetime of optical transceiver. In this paper, we will introduce in detail the. When deploying fiber optic networks, one of the most overlooked yet critical factors is the optical module temperature grade.