Introduction: Choosing the Right Ethernet Cable
When purchasing an Ethernet cable for your network, it’s crucial to focus on a few key features. Understanding these features ensures that you make an informed decision. If you’re buying an Ethernet cable for the first time, here are four important factors to keep in mind. Afterward, you can dive deeper into other considerations to further refine your choice.
1. Key Factors to Consider When Buying an Ethernet Cable
Speed (Data Rate)
The speed of an Ethernet cable refers to how much data it can transmit per second. For example, a cable rated at 100 Mbps can transmit 100 million bits of data every second. In a commercial network, your equipment typically determines the speed. For instance, a network switch with Gigabit Ethernet ports will dictate the speed. At home, choose a cable that supports your current internet speed and allows for future upgrades. Cables are categorized by their Category designation (e.g., Cat5e, Cat6), which indicates the cable’s speed. Check out Table 1: Category Cable Summary to learn more about the different categories.
Shielding
Some Ethernet cables come with shielding that protects the cable’s wires from electromagnetic interference (EMI) caused by power lines, machinery, and fluorescent lighting. Shielding also prevents the internal conductors from interfering with each other. If your cable needs to run near sources of interference, such as electrical equipment or lighting, consider a shielded Ethernet cable.
Cable Length
The typical maximum length of an Ethernet cable is about 295 feet (90 meters). Higher quality cables with better shielding and thicker conductors can reach further, but you may need to experiment a bit. Keep in mind that Ethernet runs are rarely straight lines, so plan for extra cable to account for turns. If you need to learn more, check out Ethernet Cable Length for more details.
Installation Location
Different cable jackets come with different fire safety ratings. If you’re installing Ethernet cables inside walls or between floors, choose riser-rated (CMR) or plenum-rated (CMP) cables. These jackets ensure that the cables meet safety standards. For a deeper understanding, see Jacket Ratings for more information.
2. Understanding Ethernet Cable Categories
The “Cat” in Cat5e, Cat6, etc., stands for Category. Ethernet cables are divided into categories based on bandwidth (measured in MHz), maximum data rate (measured in Mbps), and shielding.
Older Ethernet Cable Categories
- Cat1: Once the most common choice for voice telephone systems in homes and offices, Cat1 cables supported analog voice communications and had two twisted copper wires. They are no longer in use today.
- Cat2: Capable of voice and data communications, Cat2 was primarily used for IBM Token Ring networks and supported a data transmission rate of 4 Mbps.
- Cat3: Introduced in the early 1990s, Cat3 cables supported 10BaseT Ethernet networks and voice communication. Today, its 10 Mbps data rate makes it outdated for modern networking.
- Cat4: Like Cat3, Cat4 cables were used in Token Ring networks and had a 16 Mbps data rate. These cables are also outdated today.
3. Bandwidth vs. Data Rate: What’s the Difference?
Bandwidth
Bandwidth measures how many signals a cable can handle per second. For example, 1 MHz means 1 million cycles per second. Cat5 can manage 100 MHz, or 100 million signals per second, while Cat8 handles up to 2 GHz (2 billion signals per second), offering 20 times the bandwidth of Cat5.
Data Rate
While bandwidth refers to the frequency capacity of a cable, data rate refers to how much data can be transmitted. For instance, a 100 MHz cable, like Cat5, can transmit up to 100 Mbps, while Cat8, with higher bandwidth, can achieve data rates of 40 Gbps.
To improve bandwidth and data rate, manufacturers increase conductor gauge, add more twists to the wires, or introduce shielding to each conductor pair.
4. Ethernet Cable Categories Explained
Cat5 and Cat5e
Cat5 cables, introduced in 1995, support speeds up to 100 Mbps and work for 10BaseT and 100BaseT Ethernet networks. These cables can deliver data up to 328 feet (100 meters). Cat5e, or enhanced Cat5, is a common upgrade. It supports 1 Gbps and offers better resistance to crosstalk.
Cat6
Cat6 cables support data transfer rates of 1 Gbps over 100 meters and can reach 10 Gbps over shorter distances of up to 37 meters (121 feet). This higher performance comes from better shielding and an internal separator called a spline. If you need higher bandwidth, consider Cat6a, which is Cat6 augmented and supports 500 MHz bandwidth.
Cat7
Cat7 cables are similar to Cat6a but feature a proprietary GG45 connector and enhanced shielding. Cat7a offers speeds of up to 40 Gbps over 50 meters. However, due to its proprietary nature, Cat7 is less widely supported.
Cat8
Designed for high-speed, short-distance communication, Cat8 cables can handle 25 Gbps (Cat8.1) and 40 Gbps (Cat8.2) speeds over distances up to 30 meters. These cables are ideal for data centers but may be overkill for home or office use.
| Category | Max. Data Rate | Bandwidth | Max. Distance | Usage |
| Category 1 | 1 Mbps | 0.4 MHz | Telephone and modem lines | |
| Category 2 | 4 Mbps | 4 MHz | LocalTalk & Telephone | |
| Category 3 | 10 Mbps | 16 MHz | 100 m (328 ft.) | 10BaseT Ethernet |
| Category 4 | 16 Mbps | 20 MHz | 100 m (328 ft.) | Token Ring |
| Category 5 | 100 Mbps | 100 MHz | 100 m (328 ft.) | 100BaseT Ethernet |
| Category 5e | 1 Gbps | 100 MHz | 100 m (328 ft.) | 100BaseT Ethernet, residential homes |
| Category 6 | 1 Gbps | 250 MHz | 100 m (328 ft.)10Gb at 37 m (121 ft.) | Gigabit Ethernet, commercial buildings |
| Category 6a | 10 Gbps | 500 MHz | 100 m (328 ft.) | Gigabit Ethernet in data centers and commercial buildings |
| Category 7 | 10 Gbps | 600 MHz | 100 m (328 ft.) | 10 Gbps Core Infrastructure |
| Category 7a | 10 Gbps | 1000 MHz | 100 m (328 ft.)40Gb at 50 m (164 ft.) | 10 Gbps Core Infrastructure |
| Category 8 | 25 Gbps (Cat8.1)40 Gbps (Cat8.2) | 2000 MHz | 30 m (98 ft.) | 25 Gbps/40 Gbps Core Infrastructure |
5. What Type of Ethernet Cable Should You Buy for Your Home Network?
For most home users, Cat5e or Cat6 should suffice. If your Internet connection speed is up to 1 Gbps, a Cat5e cable will meet your needs. If you expect to upgrade your Internet service in the future, consider Cat6a to allow for faster speeds.
Factors to Consider for Home Use
- Cat5e: Ideal for 1 Gbps Internet speeds.
- Cat6a: Suitable for higher-speed connections (future-proofing for speeds above 1 Gbps).
- Cat6: A good balance for current speeds, especially with a Wi-Fi 6 router.
6. Ethernet Cable Length and Signal Degradation
As the length of the cable increases, attenuation (signal degradation) becomes a factor. After about 328 feet (100 meters), the signal weakens, reducing the speed and reliability of your network. For longer distances, ensure your cable is high-quality and shielded to minimize signal loss.
7. Ethernet Cable Shielding: Why It Matters
Shielded Ethernet cables can reduce interference and improve signal quality. There are two types of shielding:
- Conductor Shielding: Protects each twisted pair using aluminum foil or braided wire strands.
- Cable Shielding: Wraps all twisted pairs with foil or braided wire strands.
If your cable needs to run near electrical lines or other sources of interference, opt for shielded cables to maintain signal integrity.
Shielding is essential when you want to protect data transmission from external interference. Here are the common types of shielding used in Ethernet cables:
Shielding Types
- Unshielded Twisted Pair (UTP): Standard cables without any shielding. UTP cables are sufficient for most home environments with minimal interference.
- Shielded Twisted Pair (STP): These cables have a shield around each pair of wires to prevent interference from outside sources.
- Foiled Twisted Pair (FTP): Cables that have foil shielding around the entire bundle of wires. This offers even more protection against EMI and crosstalk.
If you install Ethernet cables near power lines, machinery, or other sources of interference, consider opting for shielded cables to maintain data integrity.
8. Ethernet Cable Connectors and Types
RJ45 Connectors
Most Ethernet cables use RJ45 connectors, which are the industry standard. 8p8c (eight positions, eight contacts) refers to a type of connector, and RJ45 is a widely used variant of it. For higher-end cables like Cat7, connectors like GG45 may be used.
Snagless Connectors
Snagless connectors prevent the clip from being damaged when the cable is unplugged. These are ideal for networks that frequently plug and unplug cables.
Special Connector Types
- M12: Used for industrial Ethernet applications that need to withstand extreme conditions like temperature and vibration.
Thank you for pointing that out! I see now where the information about RJ11, 8p8c, GG45, ARJ45, and M12 connectors was missing in my last version. I appreciate your patience. Here’s the termination section with all the missing details, now fully integrated:
Termination
Ethernet cables, which consist of four twisted pairs of wires, are typically terminated using an 8-pin RJ45 connector. This connector is the standard for most Ethernet networking applications, and it’s designed to handle the electrical signals that pass through the cable.
For older telephone cables that were based on two twisted pairs, RJ11 connectors are used. These connectors are smaller and have fewer pins (typically 6 or 4), making them suitable for telephone systems but not for modern Ethernet networks.
While the terms 8p8c (Eight Position, Eight Contact) and RJ45 are often used interchangeably, it’s important to understand the difference. 8p8c refers to the category of connectors that have eight positions and contacts, which include the RJ45 connector as a common example. The 8p8c connector design is used in various network cables, and while RJ45 is the most familiar, 8p8c connectors encompass other designs as well.
In addition to the standard RJ45, there are other connectors used for specialized Ethernet applications:
- GG45 (GigaGate 45): Developed by the French cable company Nexans for use with Cat7 cables, the GG45 connector has 12 pins in total. Eight of these pins are backwards-compatible with Cat6 cables, while the additional four pins support frequencies of up to 600 MHz. This makes the GG45 connector a high-performance option for next-gen Ethernet systems.
- ARJ45 (Augmented RJ45): This is an enhanced version of the RJ45 connector, specifically designed to support higher frequencies and provide better performance for Cat6a and Cat7 cables, enabling the cables to handle speeds up to 10 Gbps.
- M12 Coded Connectors: These connectors are used in industrial Ethernet applications, where cables are exposed to extreme conditions such as vibrations, high temperatures, and moisture. The M12 connectors are threaded for a secure connection, ensuring a waterproof and reliable Ethernet link in challenging environments.
9. Choosing the Right Cable for Special Applications
Power over Ethernet (PoE)
PoE allows Ethernet cables to carry both data and power. This is useful for IP cameras, wireless access points, and other devices that need both power and a network connection. PoE++ cables can handle higher power levels, so they are essential for demanding installations.
Outdoor Cables
If your Ethernet cable needs to run outdoors, consider CMX-rated cables, which are waterproof and resistant to sunlight.
Conclusion: Choosing the Right Ethernet Cable
Now that you understand the key features of Ethernet cables, you can make an informed decision based on your specific needs. Whether you’re upgrading your home network or building an industrial system, choose cables that match your speed requirements and installation conditions.
Snagless connectors have a modified boot that protects the connector’s lock from being accidentally snapped off. Snagless cables are typically used in situations where the cable is frequently connected and disconnected, such as a laptop-to-wall network connection.
Cable Styles
Slim and Ultra-Slim Cables
Slim and Ultra-Slim cables have a diameter that’s typically 30-50% less than that of a standard Cat6 cable. Manufactured from small gauge copper wire, the four-pair stranded cable increases airflow in crowded equipment racks, which helps keep components cool and functioning properly. The slim design also makes the cable lighter and easier to install in high-density racks, cable trays and ductwork.
Flat Cables
Although not a common choice, flat cables have some unique characteristics that make them beneficial in certain applications. Flat cables have good heat dissipation and more evenly distribute physical loads on the cable. They also bend only through the wide faces whereas a conventional round cable bends in all directions.
A flat cable is a good choice if you need to carry an Ethernet patch cable around in your laptop bag. It is strong, light and will not tangle easily. Its flat shape makes it ideal for cable runs under carpet and behind baseboard.
Solid Core Cables
Network cables are available in stranded and solid wire formats. As the name suggests, a solid core cable uses one solid copper wire for each conductor, so a 4-pair cable will have a total of 8 solid copper wires. Solid conductor cable is easy to punch down, making it ideal for structured wiring applications.
In situations where a cable is repeatedly flexed or connected and disconnected, choose a stranded cable. For horizontal cable runs not subject to repeated movement, or for Power-over-Ethernet (PoE) and outdoor applications, use solid core cable.
Armored Cable
The outer jacket of an armored cable is made from thermoplastic polyurethane (TPU), a type of polyurethane known for its strength, flexibility (even in low temperatures) and cut/abrasion resistance. Armored cable is recommended for outdoor applications and any location where the cable could potentially be crushed or cut.
What is a Crossover Cable?
There are two wiring standards used by RJ45 connectors, referred to as T568A and T568B. The difference is the pin assignment for the green and orange pairs. T568A pin-outs are the most commonly used but either will work so long as both ends of the cable are similarly wired. The U.S. Government requires the use of the T568A standard for networks installed under a federal contract.
Gauge
One of the factors limiting the length and data rate of Ethernet cable is the size of its conductors. Electrical current encounters greater resistance when transmitted over thinner wire. The larger the conductor, the easier it is for the electrons to pass through it resulting in lower resistance, lower signal loss and greater transmission distance.
The diameter or gauge of a cable’s conductor is referred to using American Wire Gauge (AWG) standard sizes. For example, a 24 AWG solid conductor is 0.0201 inches in diameter. A 28 AWG conductor is 0.0126 inches in diameter, almost half the size. That’s right, the smaller the AWG gauge, the bigger the conductor diameter.
| Cable Type | Typical Gauge | Diameter (inches) | Diameter (mm) |
| Cat8 | 22 AWG | 0.0253 | 0.6438 |
| Cat6/Cat6a | 23 AWG | 0.0226 | 0.5733 |
| Cat5e | 24 AWG | 0.0201 | 0.5106 |
| Slim Cat6 | 28 AWG | 0.0126 | 0.3211 |
| Ultra Slim Cat6 | 32 AWG | 0.0080 | 0.2019 |
Conductor gauge affects a cable’s performance but is typically not the most important factor. Shielding and twist rate have more impact on signal strength and quality.
Twist Rates
Ever wondered why an Ethernet cable uses twisted pairs of conductor wires? Early telephone lines were susceptible to interference from electrical wires that often shared the same utility poles. Engineers discovered that by swapping the position of the telephone wires every few poles (i.e. the left line became the right and the right became the left), they could reduce distortion. This technique of wire transposition was the first use of twisting, albeit with a very loose twist rate of about six turns per mile.
In 1881, Scotsman and AT&T co-founder Alexander Graham Bell used the same technique to create the first twisted pair. By the turn of the 20th century, twisted pair cable was widely used for transmission of signals on voice telephone lines.
Today, twisting conductor pairs is a common way to minimize signal interference and crosstalk, and increase cable performance. The twist rate or “pitch” is usually measured as the number of twists per inch or centimeter.
Twist Rate is not specified in the IEEE or TIA category cable standards and is left to the manufacturer to decide. Cat5e typically has a twist rate of 4-5 twists per inch whereas Cat6 cables have a twist rate of 5 or more twists per inch. To further reduce crosstalk, not all conductor pairs in a cable will have the same twist rate.
Jacket Ratings
Jackets protect the cable’s conductors from physical damage, moisture and ultraviolet light. When installing cable in walls, ceilings and under floors, it is important to use cables that meet the local code requirements (usually based on the NFPA’s National Electric Code). The three basic ratings for both cable types are general purpose, riser and plenum-rated.
| Jacket Rating | Description | Applications | Acceptable Substitute |
| CM/CMG | Communications, General Purpose | Patch cables.In-room cable runs.Not for use in risers and plenum. | CMR, CMP |
| Riser (CMR) | Communications, RiserA riser is a vertical space, typically inside walls and between floors | In-wall installationMay be required due to insurance or contractual clauses | CMP |
| Plenum (CMP) | Communications, PlenumPlenum is space above and below floors typically occupied by heating and air conditioning ductwork | Air ducts and plenums above and below floors.May be required due to insurance or contractual clauses. | |
| Outdoor (CMX) | OutdoorLDPE (low-density polyethylene) | Exterior installation.Buried or exposed to moisture or UV light.Cable runs up to 50-ft. |
Special Applications
PoE allows both power and data to be delivered over a single, solid core category cable. This makes it ideal for networking IP devices like security cameras, access control readers, wireless access points (WAPs), sensors and lighting that require DC power and a data network connection. PoE gives you the flexibility to install devices where you need them without having to worry about access to AC power.
Limited Power (LP) Applications
UL has developed a Limited Power Certification for Power-over-Ethernet (PoE) applications. The LP designation, first introduced in 2015, indicates that a cable has been tested under “reasonable worst case installation scenarios” and is capable of carrying the stated current without exceeding the temperature rating of the cable. The LP designation is particularly important in PoE++ applications where power exceeds 60 watts.
Exterior-grade CMX Ethernet cable is waterproof and resistant to drying and cracking after long-term exposure to the sun. It can also be buried in the ground without a conduit. Also consider cable and hooded connectors with an IP68 rating.
Plenum is the space above or below a room that provides a way for air to return to a building’s HVAC system. A riser is a vertical shaft between floors for electrical wiring, water pipes, and voice or data cabling. In the event of a fire, it’s critical that cabling in these areas does not promote the spread of smoke and toxic fumes.
When selecting cable to run through plenum or risers, look for products with a jacket rating of CMP (plenum) or CMR (riser). These cables have a higher degree of fire resistance and emit fewer toxic fumes compared to general purpose CM or CMG rated cables. In the US, the NFPA’s National Electrical Code (NEC) guidelines requires CMP or CMR cabling for plenum or risers and compliance may be a contractual or legal requirement. Because CMP cables have a higher fire resistance, you can use CMP in risers but you cannot use CMR cable in plenum spaces.
The jacket on these cables is constructed using an antibacterial material that is 99.9% effective in inhibiting Escherichia coli (E. coli) and Staphylococcus aureus (staph). This added protection makes these cables an ideal solution for high-touch applications and in environments where bacterial infection is of particular concern, such as medical facilities, schools, process manufacturing and restaurants/kitchens.
What is the difference between Cat5 and Cat6?
Cat6 and Cat6a cables are more expensive than Cat5e so it’s important to know what you’re getting for your money. For cable runs up to 50-ft, Cat6 is capable of 10 Gbps vs. 1 Gbps for Cat5e. For longer runs, Cat5e and Cat6 should give similar performance.
Are Cat8 cables worth the extra money?
Cat8 is designed for switch-to-switch communications in 25G and 40G networks. Residential and commercial projects outside the data center would be better using Cat6a cable. Not only is it less expensive, it’s also easier and faster to install.
Are all Cat6 cables the same?
All good quality cables that have been tested and certified by the manufacturer for a certain bandwidth and data rate are essentially the same. Shielded Cat6 and Cat6a cable will give you better performance than unshielded, particularly when cables must be run in close proximity to power lines or large electrical equipment.
Should I upgrade from Cat5e to Cat6?
Upgrading to Cat6 makes sense if the equipment on either end is capable of 10 Gbps. For example, core network connections between switches, routers or bridges would benefit from the higher bandwidth.
Can you mix Cat5 and Cat6 cable in a network?
There’s no problem in mixing Cat5e and Cat6 cable in the same network so long as you don’t create a bottleneck. Use Cat6 in the parts of your network where fast data transfer is important, such as between a switch and a router.
Do cheap cables work just as well?
In a word, no. Category cables are made of solid or stranded copper but some companies sell cheap versions made with Copper Clad Aluminum (CCA), an aluminum conductor that is coated with copper. These cables are cheaper to manufacture but result in a weaker cable that does not perform as well.