OF ALL THE APPLICATIONS for wire in a new house, nothing comes close to the complexity of the wiring needed to allow for true home connectivity. Unlike electrical cabling or telephone or cable TV wires, digital homes will require between two and five types of cable, each of which serves a specific purpose. One must be the current standard for computer Ethernet networks, CAT 5 (or CAT 6, the newer generation of the same cable). It has a maximum data speed of 100 megabits-per-second (Mbps), plenty fast for computer networks, but not fast enough for high-definition digital video and multi-channel digital sound.
So another must be coaxial cable, which, besides being the transmission medium for all cable and satellite TV services, can be used to carry any kind of digital data. It has a maximum data speed of 270 Mbps, which is sufficient for several streams of digital high-definition video and multi-channel sound, as they both exist now. The third is speaker wire—plain old copper wire, usually 18 gauge or lower for high fidelity—for whole-house audio systems, although they can be wired through a home Ethernet network if amplifiers are distributed around the home.
Then there are wires for specific applications, such as Digital Video Interface (DVI) or High-Definition Media Interface (HDMI). These are based on connection standards that were conceived to make it difficult, if not impossible, to make digital copies of entertainment programming. Finally, there is fiber, which, though almost no appliances or systems are equipped to use it today, they most certainly will be in the future. (Currently, the most common use for fiber cable in the home is as a link between DVD players or digital cable or satellite boxes and surround sound receiver/amplifiers.) Fiber has a capacity of 10 Gbps (gigabits-per-second), or 10 billion bits. Fiber would be able to handle next-generation high-definition video as well as nearly any data application a home may incorporate.
While fiber may now seem like overkill, data transmission lines have proved to be a lot like most urban periphery expressways: Build a new lane today, and it will fill up tomorrow. “I think fiber is what we are moving toward,” says Mark Younger, director of the Smart House Project at the Pratt School of Engineering at Duke University.
Installing the wire, naturally, is not enough. It must be bundled and routed in such a way that it is accessible and manageable for the future. And it must be ported into every room in the house and to every part of every digital system. This takes significant design work up front but, once reduced to a routine, should not be excessive. The answer is structured cable, which bundles all these elements into a single sheath. It is difficult to handle, but it is also easier to pull due to its 1-inch diameter. Most structured cable includes fiber and can be customized to fit the needs of a particular application.
Eaton is a maker of the junction boxes, connection modules, and wall plates that go into a structured cable system. These elements are designed for maximum flexibility in that the box, which resembles a standard electrical panel, can be configured and modified as necessary for any application with the installation of different modules for each type of wires. They also act as something akin to a patch bay in which digital data can be rerouted relatively simply.
There are claims that standard electrical wiring can be used for whole-home networking, but there are several problems associated with electrical wiring. First, it is slow, offering speeds of only 14 Mbps, which is not enough for even medium-quality digital music. Second, it is subject to interference, a problem makers of equipment that uses electrical lines for transmission say has been solved but that still concerns others. Third, the notion of consumers hooking data and audio cables through the home's electrical grid raises the possibility, however remote, of the consumer getting zapped with 110 volts AC or systems getting jolted, which could result in the loss of data. That would be particularly important to someone who had thousands of dollars worth of movies stored on a media server that got fried by an electrical short caused by a data cable.
Finally, there is wireless, which can be used, particularly over short distances. The speed for 802.11b Wi-Fi is 11 Mbps. For 802.11g it is 54 Mbps. Anew standard, 802.16, promises 269 Mbps, and utrawideband, which can cover whole cities and is sometimes referred to as Wi-Max, promises 400 to 500 Mbps. Add them all up and they still won't equal fiber.
The cost of installing a structured cable network in a new home is not particularly high. According to Richards, a rudimentary system that ports two CAT 5 lines and two coax lines into a family room, kids' bedrooms, and the master bedroom would cost around $1,100 at retail prices. Currently, this is of importance to a relatively small portion of the home buying public. But this is the generation that grew up on video games, and many are more computer savvy than your Information Technology director. It thus may behoove the prudent builder to begin installing these wiring systems, even in less expensive homes.