Using a transceiver designed for 1310 nm wavelength with a fiber cable optimized for 850 nm wavelength will result in connectivity issues and signal degradation. This is due to the fact that the optical properties of the fiber cable are optimized for a specific range of wavelengths and the light emitted by the transceiver at 1310 nm would not be properly conducted through an 850 nm optimized fiber. The core size and refractive index are matched to specific wavelength operations to minimize attenuation and modal dispersion. Therefore, it is critical to match the transceiver's wavelength specifications with the fiber cable's design to ensure optimal network performance.