Although data networking has become the glamorous end of the cabling business, installing standards-compliant telephone lines into homes and small commercial buildings remains the bread-and-butter of most cabling contractors. In the near-term future, contractors should look forward to having the Plug-and-Play House become a reality.
The Home Plug and Play, or HPnP, is designed to be the umbrella communications language under which a broad range of home-energy entertainment and security products can talk to each other. The HPnP specification will work over many types of wiring. Mainstream-electronics firms and the CEBus Industry Council, which represents more than 70 companies, back the unification effort.
The EIA/TIA 570 Residential and Light Commercial Telecommunications Wiring Standard is being revised. The existing standard has largely been ignored. But with the development of the Internet communications and other services, the TR 41.5 working group is developing what should be a more relevant document dealing just with residential wiring.
For example, some vendors are exploring the use of a multimedia residential gateway. Media include fiber optics, UTP cable (both Category 3 and Category 5), coaxial cable, wireless, and satellite dish. Also, the cabling industry is considering requiring Category 3 UTP wiring as the minimum grade of cable for all residential applications to ensure minimum performance for home computers and compatibility with future applications.
To meet demands for higher bandwidths in high-speed LAN applications, cable makers have developed "enhanced" Category 5 and gigabit-speed structured cabling systems that are rated up to 200 MHz and higher. Many industry officials believe high-frequency applications have rendered today's standards obsolete.
The EIA/TIA 568-A Commercial Building Telecommunications Wiring Standard defines the current Category 5 performance for four-pair unshielded twisted pair (UTP) cable at up to 100 MHz. However, cables performing at much higher frequencies are needed for video to the desktop, multimedia, 3-D imaging and other applications. Therefore, several new categories for copper-Category 6 rated up to 200 MHz, and Category 7 rated up to 600 MHz-have been proposed.
Presently, some of these high performance cables are sold under the designation of Level 6 and Level 7. They will all be part of the 568-A standard's next revision. Manufacturers continue to introduce enhanced Category 5 cables. And a host of products designed to meet the proposed Gigabit Ethernet standard are coming out. The problem is deciding what type of cable to install; replacing LAN cabling is difficult and expensive.
Users who specify enhanced Cat 5 are buying insurance and hoping to "future proof" their networks. UTP cable is expected to remain the dominant media for commercial telecom wiring over the next five years, during which Cat 7 products are expected to be the fastest-growing segment of the cable market. Concern over the availability of fluorinated ethylene propylene (FEP) could affect deliveries of high-performance UTP cable.
Some manufacturers don't see a repeat of the 1995 shortage of FEP, which is used in the plenum-rated version of the cable. To help dispel market confusion, cable distributor Anixter Inc., Skokie, Ill., has expanded its Levels Program for cable-performance design specification. Early in 1997, Anixter announced its Levels 97 program, in which cable is tested in its performance testing lab, in conjunction with 40 UTP cable manufacturers.
Anixter recently announced that the Levels 97 program will include connectivity and modular cable assemblies. Copper cable specified as Level 5 must meet the stricter requirements for Category 5, as defined in the International Standards Organization (ISO)11801. Level 6 must meet more stringent four-pair NEXT (power sum) requirements than Level 5, ensuring a performance level matched to the newest four-pair-based network protocols through 100 MHz. Level 7 covers a new generation of cable products that meet at least twice the Category 5 bandwidth requirement. Level 7 cable can support multiple applications at different frequencies under one jacket, and will support Gigabit Ethernet at 100 meters.
Opto-electronics and the use of optical fiber cabling will be more important in the next few years. Higher bandwidth requirements and faster transmission protocols increase the opportunities for optical fiber in a building's premises network. For example, two key inventions in photonics will be widely applied. One is the optical fiber amplifier, a device that makes it possible to magnify the reach of a light pulse without first converting that light to electrical pulses and then back into light.
The second invention is wave division multiplexing (WDM). WDM simultaneously sends light pulses of different infrared frequencies down the same tiny fiber, allowing up to 40 Gigabits per second to be sent over 16 channels. Other new technologies will allow optical fiber to deliver high bandwidth to the desktop. For example, using V-groove fiber alignment along with new fiber optic duplex connector designs, fiber can match the density of copper.