Types of Cables
Ethernet cables are broadly of two types - crossover cables and twisted pair cables.
Crossover Cable
An Ethernet crossover cable is a type of cable that is used to connect computing devices together directly, i.e. without the use of a hub or switch. These cables have different pin points or plugs on each side. The wires within the Ethernet crossover cable can reverse the transmit and receive signals. Starting from the left, the 1st and 3rd wires and the 2nd and 6th wires are crossed, and can be seen through the RJ-45 connectors at each end of the crossover cable.
Twisted Pair
This is a straight-through cable, where the pins are connected in a sequential form, i.e. pin 1 to pin 2, pin 2 to pin 3, and so on. The commonly used ones are 10BASE-T (10 Mbit/s), 100BASE-TX (100 Mbit/s), and 1000BASE-T (1000 Mbit/s). The cables that are used have four pair of twisted cables. All the three cable types support full-duplex and half-duplex communication.
Cable Categories
Cable Length(m) Speed(Mbit/s)
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Cat 3 100 10
Cat 4 100 16
Cat 5 100 100
Cat 5e 100 1 Gbps
Cat 6 100 3 Gbps
Cat 6a 100 10 Gbps
Cat 4: Cat 4 was mainly used in token ring networks, and the cable consists of four unshielded twisted-pair (UTP) wires, with a data rate of 16 Mbit/s, and a performance of up to 20 MHz.
Cat 5: This is a twisted pair high signal integrity cable. Within the cables, there are three twists per inch of each twisted pair of 24 gauge copper wires. Cat 5 is used for 10/100Mb Ethernet, and as a voice cabling format.
Cat 5e: This category is an enhanced version of Cat 5, that prevents interference between one unshielded twisted pair to another twisted pair, running in parallel within the same cable (Far End Crosstalk - FEXT). It works for 10/100Mb and 1000Mb Ethernet.
Cat 6: It is very similar to Cat 5e, and is a cable standard for Gigabit Ethernet (considered better than Cat 5e), and other network protocols that are backward compatible with the Cat 5/5e and Cat 3 cable standards. Cat 6 is made up of larger gauge wires, that work for 10/100/1000Mb Ethernet.
Cat 6a: This Ethernet cable type, known as the Augmented Category 6, works for frequencies up to 500MHz. Due to the higher frequency, alien crosstalk is eliminated. This cable type is backwards compatible with the previous versions like Cat 6 and Cat 5e.
The type of cable should be determined by your requirement, as there are many types and categories easily available all across. These cables are faster and take less processing from the CPU and other computer networking devices, which can save a lot of time during the transmission of data.
Shielded (STP) vs. Unshielded (UTP)
Because all Ethernet cables are twisted, manufactures use shielding to further protect the cable from interference. Unshielded twisted pair can easily be used for cables between your computer and the wall, but you will want to use shielded cable for areas with high interference and running cables outdoors or inside walls.
There are different ways to shield an Ethernet cable, but typically it involves putting a shield around each pair of wire in the cable. This protects the pairs from crosstalk internally. Manufactures can further protect cables from alien crosstalk but screening UTP or STP cables. Technically the picture above shows a Screened STP cable (S/STP).
Solid vs. Stranded
Solid and stranded Ethernet cables refer to the actual copper conductor in the pairs. Solid cable uses a single piece of copper for the electrical conductor while stranded uses a series of copper cables twisted together. There are many different applications for each type of conductor, but there are two main applications for each type you should know about.
Stranded cable is more flexible and should be used at your desk or anywhere you may be moving the cable around often.
Solid cable is not as flexible but it is also more durable which makes it ideal for permanent installations as well as outdoor and in walls.
