A well architected Ethernet network follows the TIA guidelines and provides interconnections from all incoming communication sources outside the facility to the edge points at the connected devices. It is advisable that a star hierarchy of nodes, and segmentations of all networks traffic is adopted at the onset. On the left shown here is a generic cabling system that depicts the relationship between the elements and how they may be configured to create a total system. The functional elements are “equipment outlets”, "Distributors" and "Cabling Subsystems", which together comprise a generic telecommunications cabling system. This is the universal TIA model for naming the parts of a network cabling system. Conceptually it starts at the bottom where “EO” stands for equipment outlet. Then there are two, and sometimes three sets of patching systems or “distributors” on the way up to the network core at the top. From the bottom up these are depicted as “DA” (Distributor A), “DB” (Distributor B) and “DC” (Distributor C). Distributor C is the patching collocated with the actual network core equipment. The cabling subsystems also start at the bottom and move up toward the network core. The links that connect the equipment outlet is “Cabling Subsystem 1”, then moving up there is Subsystem 2 and Subsystem 3 attaching the network core. Note that cabling Subsystem 1 is usually copper and subsystems two and three are usually some kind of fiber. The reason fiber links are broken into two subsystems is that these may be completely different kinds of fiber links depending on distance and environments. Shown on the right, when there is only one distributor between the equipment outlets and the core, then the cable segments would only include a subsystem 1 and 3. Alternatively when multi-zone separation requirements exist due to network propagation and complexity different type of architecture is applied to further segment the traffic and networks with different copper and fiber runs. Also note, that star topology Hierarchy should be used for generic network cabling design and that there shall be no more than two Distributors between Distributor C and an EO. (More network cabling details can be found in TIA-568-C.0)