Network Cabling


Network Cabling

The standards for Network Cabling are developed by the IEEE (Institute for Electrical and Electronic Engineers)
The standards are broken down into Categories, which must meet certain requirements.
For example; You will hear of a Cat5e Cable, this means that it is of suitable manufacture that it will allow gigabit speeds of up 100 meters.

The Categories of Cables can be broken down as follows:
- Cat5 unshielded is capable of speeds of 100Mbps up to a 100m range
- Cat5e unshielded is capable of speeds of 1Gbps up to a 100m range
- Cat6 shielded/unshielded is capable of speeds of 10/100/1000Mbps up to a 100m range
- Cat6a shielded is capable of speeds of 10Gbps up to a 100m range
- Cat7 shielded is capable of speeds of 10Gbps up to a 100m range

There are two types of Network Cabling:

- UTP (Unshielded Twisted Pair)
- STP (Shielded Twisted Pair)

Unshielded Twisted Pair is cheaper to create and maintain, however, great care needs to be taken as to where this cabling is placed. Two major issue with UTP Cabling is Radio Frequency Interference (RFI) and the other is Electromagnetic Interference (EMI). This occurs when the cabling is installed in the cross path of either of these two signals. This causes signal degradation and faulty connections.

In comparison; Shielded Twisted Pair is more expensive to maintain, and is less susceptible to the likes of Radio Frequency Interference and Electromagnetic Interference.

The standard connector for both of these types of cabling, is an RJ-45 connector. This is the connector that plugs into the Ethernet port on your Switch/Router and into the same port on your PC/Laptop.

There are two different colour codes that define the wiring layout for Ethernet cables. They are known as, T568A and T568B.

T568A                                                                 T568B

Pin 1 = White with Green Stripe                         White with Orange Stripe
Pin 2 = Green                                                      Orange
Pin 3 = White with Orange Stripe                      White with Green Stripe
Pin 4 = Blue                                                         Blue
Pin 5 = White with Blue Stripe                           White with Blue Stripe
Pin 6 = Orange                                                    Green
Pin 7 = White with Brown Stripe                        White with Brown Stripe
Pin 8 = Brown                                                      Brown

A straight through cable is where the Ethernet cable is exactly the same layout at either end, this is useful for PCs, Switches and hubs.
A Crossover cable is where each end of the cable has a different layout. So, one end will be T568A Layout and the other end will have the T568B layout. A Crossover cable is used for connecting PCs together.

After a brief check online, it appears fairly cheap in terms of cost to buy some of this equipment for testing purposes. I'm going to purchase a Crimping set and have a go at making my own Ethernet cable with RJ-45 Connector. If I go ahead with it, I'll document the process.