Specifications

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(100Mbp/s), and Gigabit Ethernet (1000Mbp/s). When Gigabit
Ethernet was being developed it was designed to operate over the
installed base of Cat5. However, real world experience showed that
not all installations were up to the task, hence the revision to Cat5e.
Cat5e is the sweet spot for any new LAN installation. Cat6 and Cat7
extend the frequency range even higher, but at additional cost. At
some point copper wiring runs out of steam and must be replaced
with fiber optic cabling.
Unshielded Twisted Pair (UTP) Category 3 and
Category 5e cabling is designed for a maximum
end-to-end distance of 100meters. This includes a
patch cord from the computer to the wall jack, 90
meters of wiring (in TIA parlance called horizontal
wiring), and another patch cord in the wiring closet
to connect facility cabling to the hub or switch.
Receptacles use type 110 terminations. This allows the cable to be quickly terminated with a punch down
tool. In the wiring closet it is common practice to connect multiple cables to a patch panel. A patch panel
consists of multiple jacks to facilitate terminating a large number of cables. From the patch panel a short
patch cable is used to connect each run to an Ethernet hub or switch.
Terminating horizontal wiring to a patch panel makes for a very flexible
installation. This is ideal when used with a large number of outlets that are
constantly being rearranged. I chose to reduce cost by terminating each
building cable directly with a Cat5 plug. Plugs are somewhat more
difficult to install then receptacles so it is not for the faint of heart. By
doing so I eliminated the cost and space of the patch panel and patch
cable. Each building cable is directly connected to the central Ethernet
hub.
The various category grades are very similar. The differences are the
number of twists per inch of the cable. Each pair of wires in the cable has a different number of twists per
inch. The higher the Category number the tighter the mechanical tolerances necessary to operate at the
higher frequency. It is important not to mix Category grades, doing so reduces the rating to the lowest
grade used.
5.2 UTP Unshielded Twisted Pair
Use of unshielded twisted pair wiring reduces the cost of network infrastructure compared to older
technology that utilized coax cable. Standard cable consists of 8 separate conductors with each pair twisted
together. To make identification easy the performance grade is printed on the cable jacket. Building wiring
uses solid wire cable. Patch cables use stranded cable to provide long flex life. Be sure plugs and
receptacles are compatible with the type of cable.
Figure 6 Cat 5 Patch Panel
Figure 7 Rear view
Figure 5 Cat 5 Jack