Building Wiring

Since the greatest percentage of upstream ingress problems occur in the drop system and internal building wiring, the communications equipment used must be designed to work in relatively “dirty” channels. One architectural choice that eliminates many inhome problems is the use of an external NID on each home that contains the data receivers and transmitters for telephony, with standard twisted-pair copper used to transport baseband analog telephony within the building. By using a NID, the network is protected from in-home ingress (see Section 17.2.3 for a general discussion of the advantages and disadvantages of the use of NIDs). NIDs may be telephone-only or, with VoIP, may terminate both voice and data services.