This part of ISO/IEC 14165 describes generic requirements for a communications transport medium called the Fabric, an entity that provides switched interconnect between pairs of user attachment points. Fabrics may be implemented using one or more topologies and this document describes requirements that are generic across all topologies. A companion document, ISO/IEC 14165-111, Fibre Channel - Physical and Signaling Interface(FC-PH), describes the physical interface, transmission protocol, and signaling protocol of high-performance serial links which attach user nodes to the Fabric. The Fabric serves to extend these serial links between pairs of attachment points. ISO/IEC 14165-111, FC-PH also describes features and behaviors of the Fabric required by user nodes.