Copper cabling has provided a reliable, flexible and economical communications medium for decades. Starting with the analog telephone and continuing with today’s high-speed digital networks, copper cabling has been the medium of choice for much of the communications infrastructure installed in today’s residential, commercial, industrial and institutional buildings. This is in spite of advances in optical fiber cabling technology and the ever-increasing demands that new applications have placed on structured cabling systems in recent years. Copper cabling continues to meet the challenge through continued advances in copper cable and connector technology.

Migration to Category 6 cabling

For more than a decade, Category 5 and enhanced Category 5 (Category 5e) unshielded twisted-pair (UTP) cabling have been the cable of choice for data applications.

However, new applications demanded improved cable performance that would provide greater bandwidth and more reliably support increased data-transfer rates. In particular, there was a need to reduce both signal attenuation and crosstalk between cable pairs to accommodate the needs of advanced applications such as Gigabit Ethernet where all four cable pairs are being used to transmit data simultaneously.

Category 6 cabling was developed to meet these needs by providing a larger copper conductor to reduce signal attenuation between transmitter and receiver as well as more pair twists and a pair divider often referred to as a “spline” to physically separate individual pairs to reduce crosstalk.

Last summer the Telecommunications Industry Association (TIA) published TIA/EIA-568-B.2.1. This industry standard defines performance and testing requirements for Category 6 components and installations. The publication of this standard paved the way for the development of new applications that take advantage of Category 6 improvements and made it the preferred choice for new installations and upgrades. According to a recent Avaya Inc. recently reported that 82 percent of enterprise network decision-makers will specify Category 6 cabling for their next installation. Users are migrating to Category 6 because it delivers higher bandwidth and improved performance that helps “future-proof” cabling infrastructure for a small increase in initial investment. Category 6 components are also fully backward-compatible with all lower cable categories.

Network-powered devices

Advances in microchip capabilities and decreased costs have resulted in more and more communication and control devices becoming “smart” and network-enabled. These devices include telephone sets using Voice over Internet Protocol (VoIP), security surveillance equipment such as cameras, access control devices, and other sensing and signaling equipment. An IEEE task force is working on IEEE Standard 802.3af, which will define the requirements for providing power to equipment connected to a structured cabling system. Currently, network equipment and stand-alone units that can be inserted into the cable run are available to provide DC power to connected network devices. Providing power directly to network devices from the structured cabling system reduces the initial installation cost and can provide a more reliable power supply than local branch circuits.

Category 7—the next generation

Category 7 cable and connectors are available from manufacturers and an international cabling standard is under development. Category 7 is a fully shielded twisted-pair cable that supports bandwidths of 600 MHz and greater. It achieves a higher performance level by shielding the overall cable and individual twisted pairs to reduce crosstalk. Category 7 is intended to support multi-Gigabit Ethernet, VoIP telephony, and other broadband applications such as video conferencing. With its individually shielded pairs, Category 7 can support mixed applications over the same cable. For example, two pairs of a Category 7 cable could be used for data, the third for telephone and the fourth for video.

Category 8—on the horizon

Proposals have also been made for Category 8, the next possible cabling category. Category 8 is intended to provide data and multimedia capabilities for small commercial and residential applications with channel lengths up to 164 feet. It will have more stringent performance requirements than Category 7 and a 1.2 GHz bandwidth for broadband applications such as cable TV.

Copper cable future

Twisted-pair copper cabling will continue to be a viable medium that will meet future needs. Innovations in cable and connector technology will allow copper cable to support applications that require faster data transfer rates and greater bandwidth. EC

GLAVINICH is an associate professor in the Department of Civil, Environmental and Architectural Engineering at The University of Kansas and is a frequent instructor for NECA’s Management Education Institute. He can be reached at 785.864.3435 or tglavinich@ku.edu.