This part of IEC 61280 provides uniform methods of measuring polarization mode dispersion(PMD) of single-mode installed links. An installed link is the optical path between transmitterand receiver, or a portion of that optical path. These measurements may be used to assessthe suitability of a given link for high bit rate applications or to provide insight on therelationships of various related transmission attributes. The principles of this document arealigned with those of the optical fibre and optical fibre cable test method, IEC 60793-1-48 (seeBibliography), which focuses on aspects related to the measurement of factory lengths.Instead, this document foc