Issue link: https://www.e-digitaleditions.com/i/1476549
36 I ICT TODAY THE PoE INFRASTRUCTURE The PoE-LED installation involves structured cabling rather than a traditional alternating current (AC) conduit installation. Where traditional AC systems require electrical cables with local power distributed to local drivers within the luminaires, a PoE infrastructure uses structured data cabling that operates on centralized power units and LED drivers connected to the PoE switch. Single-pair multidrop is defined in IEEE 802.3 as 10Base-T1S. The next step is for the Telecommunications Industry Association (TIA) to develop the specifications of the cabling, potentially enabling PoE technology to greater cost efficiency and as a mainstream solution in the future. See Figure 2. Traditional Lighting Installation PoE-Based Centralized Implementation of LED within a Future PoE Single-Pair Topology FIGURE 2: Classic LED lighting versus PoE-based lighting within a future PoE single-pair implementation. A comprehensive category cable infrastructure enables futureproofing of the building by providing a flexible and open integration for new technologies as the needs of the enterprise evolve. The installation of the category cable network is highly standardized and verifiable according to the applicable installation standards. Furthermore, PoE enables the retrofitting of buildings to support integration of technology with physical infrastructure and analytics. With a PoE topology, users have the choice between mid-span and end-span networks. The dominant end- span architecture uses a network switch that supports PoE. Mid-span, on the other hand, uses an external PoE injector installed between a non-PoE switch and a power distribution (PD) device. Both types of architecture make the transition from the old network environment to a PoE network much easier. For longer lengths, there are PoE extenders available that lessen the need for a tradi- tional local AC line voltage power source by lengthening the distance over which power can be delivered over PoE, and there are ways to daisy chain these extenders to provide power over greater distances. The latest iteration of the IEEE 802.3bt standard pushes the power level of power sourcing equipment (PSE) to 90 W by utilizing all four pairs of the category cable. Thus, PoE provides compelling benefits over conventional AC power by eliminating the need for electrical wiring and provides ease of installation, increased safety, reduced capital expenditures, and low operating costs.