Network Cabling Solutions

LITPDNCS Rev4

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Network Cabling Solutions Appendix Glossary of Terms A Administration The method for labeling, identification, documentation and usage needed to implement moves, additions and changes of the telecommunications infrastructure. Alien CrossTalk (AXT) Signal coupling from disturbing pairs into a disturbed pair of neighboring channel. Alien Far-End Crosstalk Loss (AFEXT) Signal coupling from disturbing pairs into a disturbed pair of a neighboring channel measured at the far-end. Alien Near-End Crosstalk Loss (ANEXT) Signal coupling from disturbing pairs into a disturbed pair of a neighboring channel measured at the near-end. Asynchronous Transfer mode (ATm) Technology selected by the International Telecommunications Union for broadband ISDN. This communications protocol is also specified by the ATm Forum for 155 mb/s transmission over twisted-pair cable and various bit rate optical fiber cabling applications. Attenuation A reduction in power or amplitude of the transmitted signal. In cables, it is generally expressed in decibels per unit length. Attenuation to Crosstalk Ratio (ACR) The difference between attenuation and crosstalk measured in decibels. Attenuation to Alien Crosstalk Ratio Far-End (AACRF) Difference, in dB, between the alien far-end crosstalk from a disturbing pair of a 4-pair channel, permanent link, or component and the insertion loss of the disturbed pair in another 4-pair channel permanent link or component. Previously referred to as Equal Level Far-End Crosstalk (ELFEXT) before 6A standard was released. B Backbone Cabling Cable and connecting hardware that comprise the main and intermediate cross connects, as well as cable runs that extend between telecommunications rooms, equipment rooms and entrance facilities. Balance An indication of signal voltage equality and phase polarity on a conductor pair. Perfect balance occurs when the signals across a twisted pair are equal in magnitude and opposite in phase with respect to ground. Balanced Signal Transmission Two voltages, equal and opposite in phase with respect to each other, across the conductors of a twisted pair (commonly referred to as "tip and ring"). 224 Balun An impedance matching transformer used to convert unbalanced coaxial signals to balanced signals. Bandwidth A range of frequencies, usually the difference between the upper and lower limits of the range, typically expressed in megahertz (mHz). It is used to describe the information-carrying capacity of a medium. In copper and optical fibers, the bandwidth decreases with increasing length. Optical fiber bandwidth is specified in megahertz kilometers (mHz-km). Basic Link Test Configuration Horizontal cable of up to 90 m (295 ft) plus up to 2 m (6.5 ft) of test equipment cord from the main unit of the tester to the local connection, and up to 2 m (6.5 ft) of test equipment cord from the remote connection to the remote unit of the tester. maximum length is 94 m (308 ft). Bundled Cable An assembly of two or more cables continuously bound together to form a single unit prior to installation (sometimes referred to as "loomed", "speedwrap" or "whip cable" constructions). Bus Topology A linear configuration where all network devices are placed on a single length of cable. It requires one backbone cable to which all network devices are connected. C Cable Sheath A covering over the optical fiber or conductor assembly that may include one or more metallic members, strength members or jackets. Cabling A combination of cables, wire, cords and connecting hardware used in the telecommunications infrastructure. Campus Backbone Cabling between buildings that share telecommunications facilities. Campus Distributor (CD) The international term for main cross connect the distributor from which the campus backbone cable emanates. Category 1. ANSI/TIA-568-C series of documents, the North American standards for cabling describes mechanical properties and transmission characteristics of unshielded twisted pair (UTP) cables and shielded twisted pair (ScTP) cables and assigns a unique number classification (Category 3, Category 5, Category 5e, and Category 6). 2. ISO/IEC IS 11801 2nd edition, the international standard for cabling and local standardization documents define cabling component categories based on transmission performance parameters such as attenuation and NEXT loss, over a specified frequency range. For product information visit www.hellermann.tyton.com or call 800.537.1512

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