Differences between Ethernet cables, CAT5, CAT6, CAT7, CAT8 and which ones to use

While Wi-Fi is convenient, because it leaves no cables lying around the house and allows all devices to connect to the internet, including phones and Smart TVs, there are still those who prefer to use Ethernet cables to bring the network connection to a PC or game console. Using Ethernet cables is quite simple, but if there is any theoretical and even practical doubt about which cables to use and the differences between Ethernet cables.In this guide we will therefore show you the differences that exist among the various Ethernet cables and how to use them properly, avoiding buying cables that are slow, obsolete, damaged, or unsuitable for the type of use we had planned. At the end of the guide, we will also find the buying guide to the best cables, so as to immediately choose quality cables that can cover even long distances.

READ ALSO: Better a Wifi network or Ethernet cables? which is faster?

Judas to the best Ethernet cables

There are two advantages in using cables instead of Wi-Fi: you make the most of the speed of your home internet connection (even all the bandwidth, with the right cable) and that at home we will have less electromagnetic radiation, which is important especially if we have small children or older people (although we have explained that Wi-Fi is not dangerous for humans).

Categories (or classes) of Ethernet cables

The important thing to know about Ethernet cables (also called cables RJ45) is that they are not all the same. In general, however, all cables are composed of 8 twisted wires, divided into 4 pairs, with different colors, some uniform, others with white lines. However, Ethernet cables are grouped in numbered categories (cat) based on different specifications: the higher the category number becomes, the higher its speed in Mhz is because it is more capable of eliminating interference and isolating the wires from each other. Let’s see together the categories of Ethernet cables to focus on:

• Cat. 5 is the slowest cable of the group and, even if it can handle 10/100 Mbps (Fast Ethernet) speeds up to 100 MHz, it is now obsolete; if you still use cables of this type, it is worth replacing them.
• Cat. 5e (O Cat 5 enhanced): it is currently the most used in new network systems, capable of significantly reducing interference and increasing connection speed, which reaches up to 1 Gbps (on Ethernet ports labeled as Gigabit or 1000 Mbps).
• Cat. 6/6a: It is a great improvement over Cat 5e, suitable for fast 10-gigabit ethernet networks with frequencies up to 250 MHz. Cat 6 is a cable with an internal separator that isolates the wire pairs from each other. At the moment, using Cat6 cables for the home network will make us ready for possible upgrades for the future, while still achieving greater stability in signal transmission.
• Cat. 7/7a: further evolution of Ethernet cables, with speeds of 10 Gbps and almost no interference thanks to a frequency up to 600 MHz.
• Cat. 8: the maximum evolution of Ethernet cables, with a theoretical maximum speed of 40 Gbps and frequency up to 2000 MHz.

Choosing a cable at least Cat. 6 we will have the certainty of being able to take full advantage of the Gigabit Ethernet port present on most modern modems and to take advantage of the 10Gbps ports, which is the latest technology in terms of network cables.

Shielded or unshielded cable?

Ethernet network cables are also divided into shielded (STP) and unshielded (UTP); the use of shielding in the complex and in the individual pairs of copper cables helps to further protect the cable from signal interference, especially over longer distances (over 5 meters). Let’s see below how the shields of the Ethernet cables are indicated:

• U / UTP: unshielded cable, therefore subject to interference
• F/UTP: shielded cable overall (wrapped around 4 pairs, minimum protection)
• U/FTP: cable shielded with a tape of the single pairs
• F / FTP or S / FTP: shielded cable both overall and in individual pairs
• SF / FTP: cable with double shielding both overall and in individual pairs (maximum protection)

Obviously, double-shielded cables or cables that shield both the entire cable and the pairs cost much more; for home use, it is possible to focus on cables F/UTP or, if the distance is greater than 5 meters, on U / FTP cables (leaving the cables more protected only for business needs).
Regardless of the shielding, we advise you never to exceed 100 meters of “pure” Ethernet cable, even if it is possible to overcome this distance by interposing some network switches as signal amplifiers intermediate (first 100 meters of cable, then a switch, and then another 100 meters of cable and so on).

Straight or braided cable?

Another very important thing to know about Ethernet cables is Crossover wiring or crossover cable, as opposed to the standard straight cable.

The crossover cable reverses the pairs of wires and allows you to create mini-networks by connecting two computers together without using a router or to expand a network by connecting multiple switches and routers. Unless you work as a wired network installer, most of the time it is not necessary to look at this feature to connect any device to a router or switch, while it is necessary to focus on crossed cables if we want to connect two computers. as also seen in the guide Share ADSL at home via Wifi or cable.

Other components of the Ethernet network

To complete the discussion, let’s see how the Ethernet network is composed. At the heart of any Ethernet network are three devices to which cables are connected (as already seen in the previous chapter):

• Hub: very basic device and now in disuse, since it only allows you to receive a signal on one port and transmit it to the other ports, without any type of routing.
• Switch: a device that behaves like an intelligent hub, since it examines the destination of the received packet and sends it to the right port, and only those connected to that port will be able to read it (TCP / IP routing).
• Router: the “head” of the network, since it acts as a gateway (main port) between the Internet and the local network, includes advanced features such as firewall and NAT, and also functions as a network switch if it has multiple ports.

In a home network, we will always have a modem that also acts as a router and switch, which brings the internet to computers via ethernet cables.

To learn more we can also read our guide How a router works.

Ethernet cables with electricity

Some models of Ethernet cables also carry power and are called Power Over Ethernet. In Ethernet cables of this type, unused cables are used to carry up to 25W of power: it is not a great power but it is sufficient to power small devices such as IP cameras or wireless repeaters.

To take advantage of the PoE we cannot use simple switches or home routers, but we will have to get expensive switches or a router with PoE ports so that we can use them to supply current and to be able to connect devices on the network with a single cable.

Buying Guide

In this chapter, we will show you which cables to buy based on the information seen so far, so as to choose only quality cables that can cover any distance (always within 100 meters). We will show you both the cables Cat. 6 F/UTP (for home use) and on cables Cat. 7 U/FTP (for use in small offices or over distances greater than 5 meters); for those who set up a network in an office or a large company we will show you how to choose the best cables Cat. 7 SF/FTP.

The best Cat. 6 cables (recommended in the home and small office) are as follows:

• CSL – 5m High-Quality Network Cable – Cat.6
• Techly Professional 026999 Network Patch Cable in CCA Shielded Cat. 6 Gray F / UTP 3 m
• 1,5m – white – 5 pieces – Cat6a Cable Network | S-FTP | CAT 6a | double shielding
• HB-Digital 50m Cat. 7 LAN Cabel network Ethernet Cabel Copper installation cable (loose, to be crimped)

Here below we can find the best Cat. 7 cables (suitable for office or gaming use):

• UGREEN Cavo Ethernet Cat 7
• Snowkids Cat7 3m Ethernet Cable, High-Speed ​​10Gbit / s Network Cable
• Primewire 2m High-Quality Network Cable – Cat.7
• YOREPEK Cat 7 Ethernet Cable Lan Cable 20 Meters 10Gbps

For those who want to create a modern network, here is the best Cat. 8 cables (for large business networks):

• CSL – 1m High-Quality Cat 8 Network Cable – 40 Gbits
• Primewire – 3m High-Quality Cat 8 Network Cable in Anti-kink Nylon – SFTP
• ANNNWZZD Cat 8 Ethernet Cable, 40 Gbps High-Speed ​​Patch Flat LAN Network Cable
• Veetop Ethernet LAN Cat 8 RJ45 Cable for 40 Gbps High-Speed ​​Internet Cables Network

If you need network switches suitable for any need we can find the best models below:

• TP-Link TL-SG105 Switch 5 Porte Gigabit, 10/100/1000 Mbps
• TP-Link TL-SG1016D Desktop Switch, 16 Porte RJ45 Gigabit 10/100/1000 Mbps
• Zyxel GS1900-24, Smart Network Switch, 24 Gigabit Ports, 2 SFP Ports
• Netgear GS348T Serie S350 Switch Smart Managed Pro a 52 Porte Gigabit Ethernet, con 4 SFP da 1G

To learn more we can also read the guide How to Cut (Crimp) LAN Ethernet Cables in Different Sizes.

Conclusions

Choosing a simple Ethernet cable in a market or in a small shop could hide pitfalls, especially if we do not choose one of the classes seen above and do not choose a cable adequately shielded from interference: for this reason, we suggest you choose the cables carefully. network, perhaps by helping you with the models indicated above. By choosing one of the suggested cables we will be sure to use Cat. 6 or higher network cables only, avoiding cables with older and obsolete classes.

If the line is not fast even with the new network cables we suggest you read our guides ADSL test: how do you measure internet speed? e Best Speed ​​Tests and how to use them.
If, on the other hand, Wi-Fi is slow, we suggest you read the guide Why WIFI is slow and how to fix it.