Question 1. While you were researching transmission media and costs for the medi

Question

Question 1.

While you were researching transmission media and costs for the medical

instrument manufacturer, you noticed that some of the company%u2019s telco rooms were

in disarray. For example, you notice sloppy cable terminations. Further, cables are

pulled tightly around the corners of racks and intertwined. You also suspect that the

horizontal wiring spans exceed TIA/EIA 568 recommendations. And to top it off,

cables, ports on connectivity devices, and data jacks aren%u2019t labeled. However, the

company%u2019s network manager tells you she and her staff don%u2019t have time to attend to

these oversights. What can you say to convince her that the minor oversights could

Question 2.

Thanks to your persuasive skills, the medical instrument company took a few days to improve its cable management practices. That%u2019s fortunate, because now, several months later, it has just won a huge contract and its network will expand. The brand-new warehouse is busy with activity. The inventory shelves are being stocked to the ceiling. Nearby, machines that carry merchandise along a conveyor belt are working nonstop. However, the company has a new problem: since production has stepped up, several inventory specialists in the warehouse are complaining that occasionally their handheld computers will not connect to the network or that they suddenly lose their connection. It%u2019s especially frustrating because more personnel than ever are trying to use the network. What could be causing the handheld computers to experience intermittent connectivity problems? What can you do to rule out the possibility that the handheld computers are simply faulty?

Explanation / Answer

Proper cable termination is a basic requirement for two nodes on a network to communicate. Poor terminations can lead to loss or noise-and consequently, errors-in a signal. TIA/EIA has specified two different methods of inserting twisted pair wires into RJ-45 plugs: TIA/EIA 568A and TIA/EIA 568B.

Crossover cable-A twisted pair patch cable in which the termination locations of the transmit and receive wires on one end of the cable are reversed.

Straight-through cable - A twisted pair patches cable in which the wire terminations in both connectors follow the same scheme.

Proper cable termination is a basic requirement for two nodes on a network to communicate. Poor terminations can lead to loss or noise-and consequently, errors-in a signal. TIA/EIA has specified two different methods of inserting twisted pair wires into RJ-45 plugs: TIA/EIA 568A and TIA/EIA 568B. Crossover cable-A twisted pair patch cable in which the termination locations of the transmit and receive wires on one end of the cable are reversed.

When installing horizontal cable, it is important to avoid any sources of

Electromagnetic interference (EMI), such as elevator motors, portable

Heaters, electrical wiring, air conditioning, metal beams, and walls.

Horizontal cable may be run under carpets, along ceiling tiles, over beams, frames, through wiring trays, through firewalls. Cable lengths should be tested after installation and before equipment is attached.

The best practice for installing cable is to follow the TIA/EIA 568 specifications and the manufacturer's recommendations. Be careful not to exceed a cable's bend radius, untwist wire pairs more than one-half inch, or remove more than one inch of insulation from copper wire. Install plenum-rated cable in ceilings and floors, and run cabling away from where it might suffer physical damage. If you follow both the manufacturers' installation guidelines and the TIA/EIA standards, you are almost guaranteed success. Many network problems can be traced to poor cable installation techniques.

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.