When building a wired network, Ethernet cables play a crucial role. Among the various Ethernet cable standards, Cat5 and Cat5e are undoubtedly the most common. The differences between them, as well as their relationship with other standards, are frequent concerns for users when selecting network cables. This guide provides comprehensive and clear information about Cat5 and Cat5e cables, covering their definitions, common applications, types, lengths, specifications, and pricing.

By reading this article, you will gain an in-depth understanding of Cat5 and Cat5e cables, including various connectors, testing tools, transmission speeds, cable lengths, and colors. This knowledge will help you make an informed decision based on your workplace requirements.

Cat5 and Cat5e are two common classifications for Ethernet or network cables. The Cat5e specification became widely adopted after 2001, while Cat5 was the latest standard before that.

Cat5 stands for Category 5 cable, whereas Cat5e represents Category 5 Enhanced cable. Cat5e offers significant improvements in overall performance and data transfer speeds compared to the earlier Cat5 version.

However, for users who only require moderate-speed broadband connections without demanding the highest data transfer rates, basic Cat5 cables are often sufficient.

Cat5 cables are designed to handle data transmission on Ethernet networks with frequencies (also known as bandwidth or data-carrying capacity) of up to 100 MHz. Cat5e, on the other hand, delivers superior performance with a rated frequency of up to 350 MHz. This is partly due to its stricter performance requirements regarding crosstalk (interference between individual wires), attenuation, and return loss.

In everyday use, most users primarily focus on the internet speed or data transfer speed supported by each standard.

Cat5 cables are designed to transmit data at speeds of 10 Mbps (Ethernet) or 100 Mbps (Fast Ethernet) over wired networks. When purchasing Cat5 cables online, you will often see the term "10/100 Ethernet." This means that if your local network or incoming internet connection operates at 10-100 Mbps (also known as a 100BASE-T network), a Cat5 Ethernet cable should be able to handle the required data throughput at full speed without any loss or delay.

Cat5e cables are designed to transmit data at speeds of 10 Mbps, 100 Mbps, or 1000 Mbps (equal to 1 Gbps, commonly referred to as Gigabit Ethernet) over wired connections. You will often see the term "10/100/1000 Ethernet." This means that if your local network (or incoming internet connection) operates at 10-1000 Mbps/1 Gb (also known as a 1000BASE-T network), a Cat5e Ethernet cable should be able to handle the required data throughput at full speed without any loss or delay.

In short, for transmission speeds above 100 Mbps or bandwidth requirements exceeding 100 MHz, you should upgrade from Cat5 to Cat5e or higher-grade cables. Note that all Cat5e cables are fully backward compatible with any device or port (jack) that supports Cat5 wired Ethernet connections.

From a basic structural perspective, Cat5 and Cat5e cables primarily come in two types: stranded core and solid core. These terms refer to the arrangement of the data-transmitting conductors inside the cable.

Solid conductor (solid core) Cat5/Cat5e Ethernet cables are typically used for longer-distance wiring to achieve more reliable and stable permanent wired networks. This is more common in office buildings and other professional settings. Applications involving running outdoor Cat5 cables or passing them through walls often benefit from using solid-core wiring.

Stranded conductor (stranded core) Cat5/Cat5e Ethernet cables are typically used for establishing shorter connections in temporary or easily movable wired networks. Small office networks, such as those connecting computers to routers via short Cat5e patch cables, often use stranded Ethernet wiring. Most standard Ethernet patch cables with lengths of 50 feet or shorter usually feature stranded conductors.

At first glance, without cutting open the cable to inspect it, you may not be able to tell whether a given length of Ethernet cable is stranded or solid. However, stranded cables are generally more flexible than solid ones. Solid cables tend to retain some degree of deflection after being bent at sharp angles.

The diagram on the right illustrates the basic structure of different types of Cat5e Ethernet cables.

Note that they are typically manufactured as multi-pair twisted-pair cables. They usually consist of four pairs of color-coded wires (totaling eight wires) per cable. Each pair is made up of two twisted-together conductors, forming a single strand—hence the term "twisted-pair wiring."

Beyond the basic Ethernet cable standards and the stranded vs. solid designs, each type and category has additional manufacturing specifications. These are typically abbreviated as:

• U/UTP (Unshielded/Unshielded Twisted Pair): Neither the individual twisted pairs nor the cable itself has any additional shielding. Only basic protection—the standard insulation around each twisted pair and the cable jacket itself—is present.
• F/UTP (Foil/Unshielded Twisted Pair): While the individual twisted pairs lack additional shielding, the cable features an added foil layer beneath the outer jacket.
• U/FTP (Unshielded/Foil Twisted Pair): Each twisted pair has an additional foil shield, but the cable only has the basic outer jacket.
• F/FTP (Foil/Foil Twisted Pair): Both the individual twisted pairs and the cable feature additional foil shielding.

Thus, U/UTP is most susceptible to interference, signal noise, return loss, and attenuation, but it is also significantly cheaper to purchase. F/FTP provides the highest level of protection against performance-limiting factors like crosstalk but is also the most expensive option.

The standard assembly for basic Cat5 cables is typically U/UTP, while many high-quality Cat5e Ethernet cables are manufactured with at least some form of additional shielding. This shielding helps protect transmitted signals from various forms of interference, minimizing the risk of data corruption or lost network connections.

For longer cable runs, outdoor use, or installations where cables pass through walls (which may contain numerous other electrical connections), shielded network cables are generally recommended. For shorter indoor cable runs where interference is less likely, unshielded network cables are usually sufficient.

Cat5 and Cat5e cables are available in various lengths. In most cases, Cat5 patch cables are typically chosen for relatively short wiring (100 feet or less), especially if they are stranded-core cables.

However, there are valid use cases for selecting Cat5e cabling over longer distances, where you can easily purchase spools of 1000 feet or more. Common pre-cut lengths available from UK suppliers include 30 cm/300 mm, 50 cm/500 mm, 1 m, 2 m, 3 m, 5 m, 10 m, 30 m, 100 m, 152 m, and 305 m.

Regarding the widely available colors for Cat5 and Cat5e cables, the most common options are black, gray, or white.

The price of Cat5 and Cat5e cables varies depending on the brand, quality, length, materials, and any additional shielding included during manufacturing. The cheapest Ethernet cables in this category are typically unshielded solid-core Cat5 models, while the more expensive versions are usually shielded stranded-core Cat5e cables.

You can purchase pre-made cables in specific lengths with RJ45 connectors attached at both ends. However, buying cables this way tends to be more expensive per foot (or per meter). For professional system installers, purchasing larger spools or reels of unterminated cable is often more cost-effective. You can then cut them to the desired length and easily attach connectors to the pins.

A Cat5 crimping tool is a specialized device used to attach connectors to the ends of unterminated Ethernet cables. It ensures proper contact between the wires and the connector pins, enabling reliable data transmission.

Most network cables have their category printed on the outer jacket for easy reference, typically abbreviated as Cat5/Cat5e/Cat6, etc. If your cable lacks this information, the simplest way to determine the type is by using an Ethernet cable tester.

Cat5e was introduced in 2001 as an upgrade to the previous Cat5 standard. Since then, Cat5e has become the more commonly used category in most office networking applications, offering higher bandwidth and better resistance to various forms of electrical interference.