Ethernet cables are categorized into different types based on speed and achievable length.
The commonly used network cables: Cat 5, Cat 5e, Cat 6, Cat 6a, Cat7 all have different levels of performance, and therefore it is necessary to buy or select the right cable for the right application.
There are different methods that can be used for shielding Ethernet cables. The most common is to place a shield around each twisted pair. This not only provides shielding for the cable externally but also reduces crosstalk between the internal twisted pairs as well. Manufacturers can further enhance the performance by placing shielding around all the wires in the cable just under the cable sheath. There are different codes used to indicate the differs types of shielding:
- U/UTP - Unshielded cable, unshielded twisted pairs
- F/UTP - Foil shielded cable, unshielded twisted pairs
- U/FTP - Unshielded cable, foil shielded twisted pairs
- S/FTP - braided shielded cable, foil shielded twisted pairs
Where: TP = twisted pair, U = unshielded, F = foil shielded, S = braided shielding.
A further difference within the Ethernet cables whether Cat 5, Cat 5e, Cat 6, Cat 6e, or Cat 7 can be whether solid or stranded wires are used within the cable. As the description implies, a solid cable uses a single piece of copper for the electrical conductor within each wire of the cable whilst stranded wire uses a series of copper strands twisted together. Although when buying a patch cable, it may not be necessary to know this, when installing a long cable run it may be important as each type is slightly more suitable for different applications.
- Stranded cable: This type of wire is more flexible and it is more applicable for Ethernet cables where the cable may be moved - often it is idea for patch leads at desks or general connections to PCs, etc where some movement may be needed and expected.
- Solid cable: Solid cable is not as flexible as the stranded type, but it is also more durable. This makes it best for use in permanent installations like cable installations under floors, embedded in walls, and the like.
| CATEGORY | SHIELDING | MAX SPEED (AT 100 METERS) | MAX BANDWIDTH |
|---|---|---|---|
| Cat 3 | Unshielded | 10 Mbps | 16 MHz |
| Cat 5 | Unshielded | 10/100 Mbps | 100 MHz |
| Cat 5e | Unshielded | 1000 Mbps / 1 Gbps | 100 MHz |
| Cat 6 | Shielded or Unshielded | 1000 Mbps / 1 Gbps | >250 MHz |
| Cat 6a | Shielded | 10000 Mbps / 10 Gbps | 500 MHz |
| Cat 7 | Shielded | 10000 Mbps / 10 Gbps | 600 MHz |
| Cat 8 | Details to be released later |
There are two color code standards for Ethernet Cables. 568A & 568B Standard
Straight Through or Patch cable:
These cables will have the wiring standard on both ends. That can be either 568A or 568B. Used mostly in LAN. It is used to connect dissimilar devices together.
Crossover cable:
A crossover cable is when both ends of a cable are wired using the 2 different standards. For example, one end is wired using 568A standard and the other end is using 568B standard. Cross over cables is used to connect two devices without using a switch or hub. They are also used to connect two switches together. Simply saying it is used to connect two similar devices.
When it comes to copper cabling, choosing the level of shielding you want the cable to have can prove a minefield of confusing acronyms and perplexing industry technology. We’ve put together this handy guide to help you understand the meaning of some of the most common terms.
The shielding inside your cable acts as a barrier to protect the cable from electromagnetic interference (EMI), radio frequency interference (RFI) and crosstalk between pairs and adjacent cables. It also prevents the signal from the cable interfering with surrounding equipment. The various levels of shielding offer a range of different advantages suitable for a number of applications.
U/UTP: UNSHIELDED TWISTED PAIRS
Also known as UTP, this is currently the most common and basic method of cable construction, consisting of pairs of wires twisted together. There is no shielding, instead, the symmetrical twist in the wires creates a balanced transmission line, helping to reduce electrical noise and EMI. In addition, the different twist rates of each pair can be used to reduce crosstalk. In higher category cables, a cross-web filler may be found separating the individual pairs to help reduce alien crosstalk from adjacent cables.
F/UTP: FOILED WITH UNSHIELDED TWISTED PAIRS.
Often referred to as FTP, this type of cable features an overall foil shield wrapped around unshielded twisted pairs and a drain wire. When the drain wire is correctly connected, unwanted noise is redirected to the ground, offering extra protection against EMI/RFI.
S/UTP: SHIELDED WITH UNSHIELDED TWISTED PAIRS.
This cable construction has an overall braid screen with unshielded twisted pairs. This cable is often referred to as an STP, however, this term should be used with caution due to other shielded cables also using this term. Always check whether the cable will have any shielding and whether individual pairs have their own shield. The cable is capable of supporting higher transmission rates across longer distances than U/UTP and provides better mechanical strength and grounding due to the braid.
SF/UTP: SHIELDED AND FOILED WITH UNSHIELDED TWISTED PAIRS.
This cable has both an overall braid shield and a foil shield with unshielded twisted pairs. This cable offers effective protection from EMI both from the cable and into the cable as well as much better grounding due to the additional braid.
U/FTP: UNSHIELDED WITH FOILED TWISTED PAIRS
This type of cable has no overall shielding but the individual twisted pairs are wrapped in a foil screen, offering some protection from EMI and crosstalk from adjacent pairs and other cables.
F/FTP: FOILED WITH FOILED TWISTED PAIRS
This type of cable features an overall foil shield with individually foil tape shielded twisted pairs. These are similar to F/UTP cables, with the addition of a foil shield around each twisted pair. The cable construction is designed to provide the assembly with greater protection from crosstalk from adjacent pairs and other cables, RFI and EMI.
S/FTP: SHIELDED WITH FOILED TWISTED PAIRS
Similar to F/FTP, the individual twisted pairs are wrapped in a foil tape before being wrapped in an overall flexible yet mechanically strong braid screen. The additional foil on the twisted pairs helps to reduce crosstalk from adjacent pairs and other cables. The braid provides better grounding.
SF/FTP: SHIELDED AND FOILED WITH FOILED TWISTED PAIRS
Offering the maximum protection from RFI/EMI, crosstalk, and alien crosstalk, this cable has both an overall braid shield and foil shield, with individually foil tape screened twisted pairs. This type of cable provides the best level of protection from interference and better grounding due to the braid.
THE ACRONYM STRUCTURE DISASSEMBLED
Sources:
[1] https://www.universalnetworks.co.uk/faq/what-does-utp-s-utp-ftp-stp-and-sftp-mean/
[2] https://www.electronics-notes.com/articles/connectivity/ethernet-ieee-802-3/cables-types-pinout-cat-5-5e-6.php