How time
flies.....it’s coming to our 5th lecture class for telecommunication
&networking .....
Yes, time is
cruel, it doesn't wait for anyone. Can you believe that we
had already go through almost 1 semester?? Can you believe that we
had gone through the first quarter of 2012 already?
had already go through almost 1 semester?? Can you believe that we
had gone through the first quarter of 2012 already?
All assignments and homework suddenly say 'HI' to me and this had made me feel exhausted......T^T
I wish I can make the clock stop ticking right now.....>.<
So, I think it is the time for me to study hard since final
exam is just around the corner…..
Ok, back to the topic…the topic for 5th lecture
class was CABLING…^^
Cabling sounds interesting for me..... o(^.^)o
First, you all may wonder what is
the correct definition for cable……
Well, cable is the medium through
which information usually moves
from one network device to another
.
Several types of cable are commonly
used with LANs.
In some cases, a network will utilize
only one type of cable, while other networks will use a variety of cable types.
There are 4 types of cables:
1) Unshielded Twisted Pair (UTP)
Cable
2) Shielded Twisted Pair (STP)
Cable
3) Coaxial Cable
4) Fiber Optic Cable
Unshielded
Twisted Pair (UTP) Cable
The cable has four pairs of wires
inside the jacket. Each pair is twisted with a different number of twists per
inch to help eliminate interference from adjacent pairs and other electrical
devices.
The standard connector for
unshielded twisted pair cabling is an RJ-45 connector. (RJ means registered
jack)
A disadvantage of UTP is that it
may be susceptible to radio and electrical frequency interference.
UTP Cable |
Shielded
Twisted Pair (STP) Cable
STP is a type of cable consists
of two individual wires wrapped in a foil
shielding to help provide a more
reliable data communication.
Hence, it is suitable for
environments with electrical interference.
The disadvantage is the extra
shielding can make
the cables quite bulky.
STP is often used on networks
using Token Ring topology.
Coaxial
Cable
Coaxial cabling has a single
copper conductor at its center.
A plastic layer provides
insulation between the center conductor and a
braided metal shield.
The metal shield helps to block
any outside interference from fluorescent lights, motors, and other computers.
Fiber
Optic Cable
Consists of a center glass core
surrounded by several layers of protective materials
It transmits light rather than
electronic signals eliminating the problem of
electrical interference.
It is ideal for certain
environments that contain a large amount of electrical interference..
Fibre optic cable is superior
than others since it is able to transmit signals over much longer distances
than coaxial and twisted pair.
Fiber Optic Cable |
Now, I am going to share a video so that all of you will be able to get a clearer image about fiber optics.
Summary
for Ethernet Cabling:
10 Base T: Unshielded Twisted Pair : 100
meters
10 Base 2: Thin Coaxial : 185 meters
10 Base 5: Thick Coaxial : 500 meters
10 Base F: Fiber Optic : 2000 meters
Cable
and Topology:
Linear Bus : Coax, twisted pair, Fiber : Ethernet, Local Talk
Star : Twisted pair, Fier : Ethernet, Local talk
Star-Wired Ring : Twisted pair : Token Ring
Tree : Coax, Twisted Pair, Fiber ; Ethernet
Linear Bus : Coax, twisted pair, Fiber : Ethernet, Local Talk
Star : Twisted pair, Fier : Ethernet, Local talk
Star-Wired Ring : Twisted pair : Token Ring
Tree : Coax, Twisted Pair, Fiber ; Ethernet
That's all for this week's lecture.....see ya.....^^