TX and RX in SFP refer to the transmission (TX) and reception (RX) of data signals over a fiber optic cable using Small Form-factor Pluggable (SFP) modules. TX converts electrical signals into optical signals while RX converts optical signals back to electrical signals. These modules, including SFP, SFP+, and SFP28, are widely used in enterprise networks, data centers, and carrier-grade deployments. In single-mode fiber, typical transceivers using 1310nm wavelengths (e. These links can span 10 to 15 kilometers.