While they're designed to operate within specified temperature ranges, running a module above its rated operating temperature causes measurable performance degradation and can lead to permanent failure. When the operating temperature of an optical module exceeds its design range, it will not only affect its performance, but may also cause serious problems such as. Optical transceivers (SFP/SFP+/QSFP/QSFP28 and similar) are the backbone of modern fiber networks. Three Key Temperature Ranges & Applications Mission-critical applications in industries like oil and gas, transportation, and military. Commercial-grade transceivers are designed for stable.