For intra-building cabling, the most critical step is identifying the location of communications closets. They should be located to minimize individual cable runs to every location. Also, managers should ensure that closets are not near any electromagnetic interference source, such as power transformers or copying centers. Ceiling distribution or floor distribution systems are the two most common approaches for intra-building cabling. The ceiling-distribution approach uses space between the structural floor and the suspended ceiling.
Cables run down along the walls or wire poles and terminate at the power or communication outlet.
Ceiling distribution offers a high degree of flexibility for future additions and changes and allows easier access for a large portion of the service area. Floor-distribution systems use conduits or channels under floors and can be used with raised or cellular floors. Under-floor systems can have separate channels to accommodate both power and communication systems in the same assembly, reducing the overall cost. They can be encased in concrete and accessible through junction boxes, and they provide a high degree of security. An integrated solution Using a consolidated approach in designing common cable pathways can reduce initial construction costs by 10-30 percent.