Friday, 27 April 2012


How time’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?
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

That's all for this week's lecture.....see ya.....^^