Whether it getting a LAN cable for home use, or selecting a LAN cable while planning for industrial needs or business network infrastructure, you may have questions on which cable to use. You may notice that there are several types to choose, namely Cat 5, Cat 5e, Cat 6, Cat 6a, Cat 7, Cat 7a, up to the latest Cat 8. The Cat ratings stand for category and the different numbers represent different speed and specifications for each type of cable. The higher the number, the newer the technology and the higher the data rate supported.
Basic differences to look for across the categories would be:
To generalize, Cat 5 is mostly obsolete now as it only goes up to 100Mbps. Cat 5e is suitable for installation in residences and in small offices with network speeds below 1Gbps. It supports bandwidths from 100 MHz up to 350 MHz. An easy way to think of bandwidths would be similar to traffic flow; the wider the road or higher the bandwidth, the more cars or data can pass through at a go. In Cat 5e, the pairs are twisted together tighter than Cat 5 to reduce crosstalk (the interference caused by electromagnetic signals affecting another electronic signal).
Cat 6 is recommended for larger installations like university campuses and big office buildings.
Cat 6 can support 1Gbps up to 100 meters, and can also support 10Gbps up to 55 meters. It supports bandwidths up to 500 MHz. The pairs are twisted even tighter than Cat 5e to help with crosstalk. Keystone Cable’s Cat 6 also comes with a spline between the pairs to further minimize crosstalk.
Cat 6 comes with the option of being shielded to improve performance (earlier network cables were all unshielded). For example, an unshielded twisted pair cable would be satisfactory for a short run between a computer and router, but a foil shielded cable is better for longer runs or where the cable would pass through areas of high electrical noise, such as in an industrial factory.
At Keystone, our Cat 6 common stock includes U/UTP (Unshielded/ Unscreened twisted pairs) and F/UTP (Overall foil shield / Unscreened individual twisted pairs).
Cat 6a is suitable for industrial, commercial and data center applications.
Cat 6a handles 10Gbps up to 100 meters and supports up to 500 MHz of bandwidth. The pairs are twisted even tighter than Cat 6 to help with crosstalk and allow the higher bandwidth. It is also common to find each pair individually foil shielded, as well as with an overall braided shield.
At Keystone, our Cat 6a common stock includes S/FTP (Overall braided screen / Individual foil screened twist pairs).
Cat 7 and Cat 7a are commonly found in bandwidth intensive applications like data centers, or other places where the extra interference protection is needed.
Cat 7 and Cat 7a handle 10Gbps up to 100 meters and supports bandwidth up to 600 MHz. What helps this category cable perform better than the previous ones are more strict and precise manufacturing processes to increase the tightness of the twists, in addition to the individual shield and the overall shield to dramatically reduce crosstalk and interference. Cat 7 and Cat 7a have shown in test results to deliver 40 Gbps over distances up to at 50 meters and 100 Gbps up to 15 meters.
The one drawback for using Cat 7 or 7a may be that it is not recognized by EIA/TIA (wiring standards for commercial and telecommunications wiring), and uses its own proprietary non-RJ45 connector, which may be more difficult to purchase as well.
At Keystone, our Cat 7 common stock includes SF/UTP (Overall braided and foil screened / Unscreened individual twisted pairs).
Cat 8 is new and explored for use between servers and switches in large data centers where there is an insanely high bandwidth requirement.
It is currently uncommon to use Cat 8, although it does jump several iterations in performance. It can handle 25Gbps/ 40Gbps up to 30 meters and supports bandwidth up to 2000 MHz.
The development of Cat 8 is sub-divided into Cat 8.1 and Cat 8.2 under IEC standards. Cat 8.1 is backward compatible with Cat 6a, Cat 6 and Cat 5e while Cat 8.2 is backward compatible with Cat 7 and Cat 7a. This is due to the connector relationship where Cat. 8.1 uses a standard RJ45 while Cat 8.2 uses a non-RJ45 connector.
As a rule of thumb, your network is only as fast as the slowest part in your entire channel. For example, if your internet connection is 300 Mbps but your router’s ports can transfer only 100 Mbps, then your whole network would then be limited to 100 Mbps instead of the full 300 Mbps. Hence when you consider the Cat type, you would need to scrutinize the rest of your system to ensure compatibility. However, we do recommend future proofing especially if you intend the cable installation to be concealed within walls. In such cases, we recommend getting a LAN cable that is one step higher than your current requirements to future proof your installation.