A simplified description of a network is the connection of various devices to each other.  There are various ways of connecting these devices together, but mainly one can look at a wireless or wired connection.

What is Ethernet?

Ethernet is a system that connects various devices together via cabling that creates a network.  To simplify things one can look at ethernet as the plumbing pipes of the network or the internet, where water (data) passes between one area to the other.

The term ethernet was co-invented by Robert Metcalfe.  It defines the entire range of twisted pair and fibre cables that are central in any network.  These cables are constantly upgraded to improve both bandwidth speeds, ie the speed with which data is transferred, as well as noise cancellation.   These improvements on ethernet cabling are standardised by the Institute of Electronics Engineers (IEEE).

Ethernet Types.

Differences in the different types of ethernet cables are not visible to the untrained eye.  Each new improved generation of cable introduces copper pairs with tighter twists and more complex sheathing.  This improves both data transfer speeds and noise cancellation.  The latter increases the distances of cable between two devices.

With each new standard older cables becomes obsolete.  However backward compatibility exists between the standards.

The current cables in use are mainly; Cat5e, Cat6, Cat6a and Cat 7.  There is a new standard, Cat 8, which will be in use in the near future.  For this article we shall be looking into the network cables most widely available today ie Cat5e, Cat6, Cat6a and Cat 7.

Category 5e

Cat 5e has been in use for almost 20 years.  At the time it was standardised it gave us the first possibility of looking at network speeds of 1 Gigabit, even hardware to utilise such speeds was very expensive at the time.
With time the price of hardware that could utilise such high speeds started becoming more affordable.  Our view is that today 1 Gigabyte networks should be the minimum setup.  

Cat 5e cables are normally made out of 24 gauge twisted pair wires, which can provide a Gigabit network of distances of up to 100m.

Category 6

Cat 6 cables were introduced a few years after Cat5e.  The Cat 6 offered speeds of upto 10Gbps.  The standard for much of the 2000s was to use Cat5e between workstations, and CAt6 were utilised at the core, that is connection between routers and switches.  
The 10 Gigabit capabilities of the Cat6 cables is limited to 50m, after which the max speed is similar to Cat5e 1 Gigabit.

The Cat 6 uses a tighter twist allowing for two-way communication on the same wire.  This means that even at longer lengths were speed goes down to 1 Gigabit, the Cat 6 network cable has less delays, thus it would run faster.

Beyond the speed/distance factor, Cat 6 has a tighter twist in the cables, which allows for two-way communication on each pair of wires, where Cat5e does not allow this feature. We have noticed that in certifying our cable installations, Cat 5e cable has a tendency to have a higher delay and skew than Cat 6 cable. That means that even though both Cat5e and Cat 6 can do 1 Gigabit networks, Cat5e may have a longer delay for the signal to get from one side to the other, which will give the appearance that it runs slower.

Category 6a

Cat 6a is visually thicker than Cat 6.  This is due to various factors; there is added thickness to the plastic covering the wires themselves and tighter twist in the pairs themselves, thus having more copper per metre.  

Cat 6a offers speeds of 10 Gigabit over a distance of 100m.  One also has to point out that Cat 6a reduces crosstalk between the pairs, thus reducing the delay in the cables.

Category 7

Cat 7 supports 10 Gigabit speeds, however testing has shown that speeds of upto 40 Gigabits are achievable at distance of less than 50m, with some sources even quoting speeds of upto 100 Gigabits over 15 metres.  

Cat 7 also offers extensive shielding which reduces signal attenuation.  Physically the cables are stiffer than previous standards.
The shielding for Cat 7 ethernet cables needs to be grounded, and they require special Gigagate (GG45) connectors.

How to choose the right network cable

This article is aimed at giving a basic idea of the different types of ethernet cables.  Which standard applies for your needs, depends on a host of variables.  Intertek Labs can help you choose the right solution for your needs, both current and future.