Ethernet (UTP) Cable

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For computer networking purpose most commonly used cable is ethernet cable. Ethernet cable is mainly two types, UTP and STP. UTP stands for Unshielded Twisted Pair and STP stands for Shielded Twisted Pair. Among those UTP is used for most of the networking purpose. Depending on the network devices, UTP cable is two types- straight and cross. Here is a short description on this network cable.

Figure: Network Cable (UTP - Unshielded Twisted Pair)

Generally mainly used two types of UTP cable.
1. Category 5 (Cat 5) 
2. Category 6 (Cat 6)

In UTP, there are total eight (8) cables in four (4) pairs. Those are

Internationally there are two types of standard to make straight and cross cable.
1. T-568 A (generally called  standard A)
2. T-568 B (generally called  standard B)

Note: From the above design it can be observed that , if  interchange 1,3 and 2,6 then A change into B or B change into A.
Or simply interchange between Green and Orange cable.
Cross cable or Cross over cable

When both end of a UTP cable has same type than it called straight cable. See the example below.

                         Or 
Usage of Cross Cable
It is used to connect same layer devices. As for example, if you want to connect two laptops or two PCs then you have to use Cross cable.
Straight cable or Straight through cable
When both end of a UTP cable has different type than it called cross cable. See the example below.
Usage of Straight Cable
It is used to connect different layer devices. As for example, if you want to connect one switch
(any switch) to one laptop then you have to use Straight cable.

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