Networking twisted pair (TP) cables are types of cables that come in pairs that are twisted. The twisting is used to reduce crosstalk and electromagnetic interference. They are the most common types of ethernet, CCTV, and telephone networking cable. They are simple to configure and cheaper compared to other types of guided networking media.
Twisted pair cables are cheap and simple to configure and use. However, they have low data transmission speeds and suffer from electromagnetic interference. They are characterized by having pairs that are twisted and color-coded. Cables are also categorized depending on the speed and distance of data transmission.
Types of twisted pair cable
Networking twisted cables come in 2 types depending on if they are shielded or not. They include shielded and unshielded pairs.
- Unshielded twisted pair (UTP): this is a twisted cable that doesn’t have a shield to reduce electromagnetic interference. They are cheaper but they have high attenuation and noise interference.
- Shielded twisted pair (STP): the cable has an aluminum foil shield after the outer jacket. It has better tolerance to interference but is a bit expensive compared to unshielded. The STP is mostly used on outdoor operations where we have more interference and other environmental elements.
Advantages of twisted pair cables
- They are the most common network cables that are simple to use and configure. In most buildings that had networking, these are the types of cable you will find.
- Twisted pairs are cheaper compared to other network cables like coaxial.
- They have relatively fast data transfer when used in the Local Area Network. Category 6 types of cable can support speeds of up to 10Gbps.
- Twisted cables are used to transmit both audio and other multimedia data.
Disadvantages of twisted pair cables
- The cables are affected by electromagnetic interference and noise. This is high on unshielded twisted pairs.
- They cover a short distance before the signal is distorted. The attenuation is around 100 meters. After that, the signal becomes weak and should be boosted.
- Twisted pairs have limited bandwidth when compared to other types of cables such as coaxial or fiber cables.
- They are sensitive to eavesdropping and other security attacks.
- Low data transmission rates. The latest cable categories have high transmission speeds but for a shorter distance.
Parts and components of twisted cable
- Outer jacket: this is the outer plastic cover that protects the cable from environmental elements.
- Braided or foil shield: this is a metallic mostly aluminum shield that is used to reduce electromagnetic interference.
- Copper cable: this is the copper wire that is used to transmit signal and data.
- Pair shield. This is a shield that covers each pair specifically.
Characteristics of twisted pair cable
- Just as the name suggests the 2 pairs are twisted to reduce interference.
- They come in pairs. The pair can range from only two up to the number that the client request. However the most common is a 4-pair cable, which has 8 copper wires in it.
- The pairs are color coded which is used when the cable is being terminated. Depending on the function of the cable terminated the termination used a different type of standard.
- They are classified using categories depending on the data speed that they can support and the distance data travel before it becomes weak.
Twisted pair cable color code
The most basic horizontal color code has 4 pairs which are 8 wires. Each pair is arranged to have one wire have a solid color while the other has the color and white stripes.
The first pair has white/blue and blue, followed by white/orange and orange, white/green and green, and white/brown and brown.
When the cables are being terminated to a connector and port such as RJ45 they use 2 of the most common wiring standards 568A or 568B wiring schemes. Depending on the standard that you choose the color will move in different pins of the RJ45.
Categories of twisted pair cables
The twisted pair cables are grouped into 5 categories according to the type of data transmitted, and the maximum rate of transmission.
|Category||Data transmission rate||Suitable for transmitting|
|Cat1||Less than 1 Mbps||Voice|
|Cat6||200 Mbps and above||Data|
Application/ uses of twisted pair cable
- TP cables are used for home and office networking.
- They are used in CCTV camera security networking.
- For those institutions that still used intercom twisted pairs are the most preferred types of cabling.
- Twisted pairs are used with RJ45 or RJ11 ethernet connectors.
What is the function of twist in twisted pair cable?
It prevents electromagnetic interference and cross-talk. When signals are sent through the cable, they are affected by electromagnetic signals from the adjacent cable and other external factors. When the cable is twisted they cancel this effect. This is just one way of reducing the noise but not the only way.