TIA 559-1 : 1992(R2002)

In some applications, the immediate requirements for transmission capacity in terms of length and bandwidth may be modest, and operation at short wavelengths may be advantageous, for economic or other reasons. Nevertheless, high-capacity single-mode fiber may need to be deployed in anticipation of future upgrading to broadband transmission. Such a scenario may lead to short-wavelength transmission over Class IVa fiber. The system engineering methodology outlined in this document can be applied to such a system, subject to certain modifications outlined in this Appendix.