1 Overview of Trunk Cabling

The function of trunk cabling is to provide connections between management areas, devices, and devices in the integrated cabling system, such as at the entrance. The trunk wiring consists of the transmission media required by the population equipment between the devices, the main jumper box, and the mechanical terminal to form the mutual connection of the communication equipment. Computers, equipment, demarcation points may be distributed in different buildings, trunk wiring is the transmission media between buildings.

It is obvious that it is not possible or economical to pre-install all main lines for a permanent cabling system. The effective installation of trunk lines is generally expected to be divided into seven design phases, each of which takes 3 to 10 years. No additional wiring can be installed at each stage, ensuring that it accommodates growth and changes in business requirements. The length of each stage depends on the stability and variation of the units used.

Before each design phase begins, it is necessary to delineate the maximum amount of wiring required for that phase. For each management area, between devices, and for different types of services, the total amount of large-scale connections during the design phase should be estimated. Sufficient BACKBONE WIRING FOR COPPER OR FIBER OPTIC MEDIA TO SATISFY A LARGE NUMBER OF connections, EITHER DIRECTLY or THROUGH AUXILIARY ELECTRONICS. When designing lines and supporting trunk cable structures, care should be taken to avoid electromagnetic interference generated by engines and transformers.

2 Trunk wiring topology

(1) Star topology

Backbone cabling uses the common hierarchical star topology, with cabling to a main hop or inner hop to main hop in each management area. There are only two types of hops commonly used in trunk wiring. The two management intervals must be connected through at least three hops. A single hop must reach the main hop.

A separate trunk wiring hop box (main cross connection) may satisfy the need for cross connection. The trunk wiring can be jump-connected in the cabinet, equipment room, or in-building equipment.

Note 1: THIS topology has been adopted as a standard topology because of its compatibility and stability to meet different usage requirements. The restriction of hop boxes for the two standards is to limit the signal attenuation of the old system and strengthen management.

Note 2: The star topology is suitable for dedicated units that transmit media, such as dedicated fiber, twisted pair, or coaxial cable. According to the actual characteristics of the field and equipment room, the transmission media connected to the terminals of different devices is part of the same cable in a distance. Special cables can also be used at this distance.

Note 3: The bridge wiring is not attached to the main wiring.