Coaxial Cable:
Coaxial cable, often referred to as BNC cable (the initials refers to
the Baynonet-Naur Connector-a byonet-shaped for thin coaxial cables), is
made of a single copper wire encased in insulation and then covered
with a layer of aluminum or copper braid that protects the wire from
outside interference. If you need more bandwidth and noise protection
than twisted-pair can provide, but can’t afford fiber-optic, coaxial
cable is the way to go.
Coaxial cable has four parts:
· Inner conductor: A central wire
· Dielectric: A layer of insulation that surrounds the inner conductor.
· Shield: A layer of foil or metal braid that covers the dielectric.
· Jacket: A final layer of insulation.
If
is a popular cable for the connective of the computer terminals. It
consist of the two conductor surrounded by two insulting layers. The
first layer of insulation encloses a central copper conductor wire. This
layer has an outer shielding conductor braided over the top of it.
Coaxial Cable prefer mostly bus topology network. Each device must be
connected to a T-connector. Each T-connector is connected to the next
with a coaxial cable. After all of the devices are connected, the ends
of the cable must then be terminated with terminator, a coaxial network
is configured in a bus topology.
Four varieties of coaxial cable are available. Each is used with different types of LAN:
· Ethernet:
used frequently as a backbone for large coax networks. Often referred
to as 10Base5,a standard set by the institute for Electrical &
Electronics Engineer (IEEE), and also called Thicknet.
· RG-58A/U: Used in coax Ethernet networks. Often referred to as 10Base2 and also called Thicknet.
· RG-59/U:Used on CATV (Cable TV) and ARCnet (an older network topology).
· RG-62/U:Used on ARCnet and IBM terminals .
