 higher the number, the smaller the diameter. You may also see the term AWG which stands for American Wire Gauge. Most telephone cable is either 24 or 22 gauge. Twenty-four gauge is typically used for premise cabling, while 22 gauge is used to connect telephone company central offices. Fiber optic cable now more commonly connects most central offices. The Telecom Handbook CHAPTER 12 The telephone closet in which the riser cable is terminated is usually located in some common building area, perhaps adjacent to the elevators. It is typical to take the outside lines from the building telephone closet and run them through a cable in a con- duit (pipe) into the telephone equipment room. There the PBX and perhaps the file servers for the LANs are located. This PBX room is part of the individual business' premise. The plastic and metal blocks on the wall of the telephone equipment room on which the outside lines are terminated are referred to as the demarc. The blocks at the demarc are also called the RJ21X's or just RJ's. This is the point of demarcation where the outside lines are dropped off. From that point the telephone system installation company runs cable to connect the outside Recommended Cabling Practices DON'T Terminate each horizontal Use connecting hardware cable on a dedicated that is of a lower category telecommunications outlet. than the cable being used. Locate the main cross- Create multiple appear- connect near the center ances of the same cable of the building to limit at several distribution cable distances. points (called bridged taps). Maintain the twist of horizontal and backbone Over-tighten cable ties, cable pairs up to the point use staples, or make sharp of termination. bends with cables. Make sure that horizontal Place cable near equipment cables are all the same that may generate high category or higher. levels of electromagnetic Tie and dress horizontal interference. cables neatly and with a maximum bend radius of 4 times the cable diameter. - Compliments of Dave Crozier The Telecom Handbo