Category 4 Cable

Definition of Category 4 Cable

Category 4 cable, often referred to as Cat 4, is a type of twisted pair cable used primarily in telephone and data communication systems. It supports data transfer rates up to 16 Mbps and has a maximum frequency of 20 MHz. Although Cat 4 was once popular for Token Ring and 10BASE-T Ethernet networks, it has largely been replaced by higher category cables like Cat 5e and Cat 6 due to their improved performance capabilities.


The phonetics of the keyword “Category 4 Cable” is:/ˈkætɪɡəri foʊr ˈkeɪbəl/- Category: /ˈkætɪɡəri/- 4: /foʊr/- Cable: /ˈkeɪbəl/

Key Takeaways

  1. Category 4 cable, also known as Cat 4, is an older type of Ethernet cable that provides data transfer speeds of up to 20 Mbps on computer networks.
  2. Cat 4 cables were primarily used in Token Ring and 10BASE-T Ethernet networks, though they have become obsolete due to newer and faster cable standards like Cat 5, Cat 6, and Cat 7.
  3. Despite being considered outdated, Cat 4 cables can still be found in some older installations and buildings, but upgrading to a more modern cable standard is highly recommended for improved network performance and reliability.

Importance of Category 4 Cable

Category 4 cable, also known as Cat 4, is an important technology term because it played a significant role in the development of data communication systems during the 1990s.

It was one of the early Ethernet cables that provided a substantial improvement in performance over its predecessors, facilitating data transfer speeds of up to 16 megabits per second (Mbps) with a maximum bandwidth of 20 MHz.

As a part of structured cabling systems, Cat 4 cable was widely used in the deployment of Token Ring networks and 10BASE-T (10 Mbps) Ethernet connections.

Although it has now been surpassed by more advanced cable categories, Cat 4’s contribution to the growth of early network infrastructure is undeniable, laying the groundwork for current high-speed data transfer technologies.


Category 4 cable, also known as Cat 4, was a significant advancement in the data communication industry during the 1980s and early 1990s. Designed primarily to support a transmission speed of up to 16 Mbps (megabits per second), this level of bandwidth was sufficient in addressing the networking needs of businesses and homes at the time.

Characterized by its twisted pair construction, Cat 4 cable represented a shift toward higher-quality, noise-reducing cables, allowing analog voice and digital signals to transmit simultaneously. The primary applications included Token Ring networks, used extensively during the period, and 10BASE-T Ethernet networks, a precursor to the faster and more prevalent Ethernet standards in use today.

Although Cat 4 cabling provided a significant improvement over its predecessors, it has since been largely replaced by more advanced cable types, such as Category 5 (Cat 5), Category 5e (Cat 5e), Category 6 (Cat 6), and Category 6a (Cat 6a) cables, which offer dramatically improved data rates and overall performance. Nevertheless, the advent of Category 4 cable paved the way for further research and development in the field of data communication technology, particularly in addressing the ever-increasing demands of today’s digital world.

The innovations spurred by Cat 4 cables continue to aid in the advancement of the industries that rely heavily on high-performance, reliable networking capabilities, including healthcare, finance, and telecommunications.

Examples of Category 4 Cable

Category 4 (Cat 4) cable is an older type of network cable used primarily for data transmission in local area networks (LANs). Here are three real-world examples of where Cat 4 cable has been used:

Token Ring Networks: In the late 1980s and early 1990s, Cat 4 cable was popularly used in Token Ring networks, a type of LAN that employed a token passing method for channel access control. Token Ring networks were implemented in many businesses and educational institutions during this time, as an alternative to Ethernet networks.

Telephone Systems: Cat 4 cable was also used in some telephone systems, especially in large businesses and institutions, when voice traffic was transmitted over the same cabling infrastructure as data. Cat 4 cable was used for connecting phone lines, patch panels, and distribution frames, to help distribute and manage multiple telephone lines within an organization.

Legacy Network Upgrades: Some older LANs that were initially installed with Category 3 cable, a slower and less reliable cable type, were eventually upgraded to Category 4 cable to improve network performance and support higher data transmission rates. Cat 4 cable was an intermediate solution until the newer and faster Category 5 cable became the industry standard.It is worth noting that Category 4 cable is now considered obsolete for modern networking installations, as it has been surpassed by the newer and more efficient Category 5, 5e, 6, and 7 cable standards.

FAQ: Category 4 Cable

What is a Category 4 cable?

Category 4 cable, also known as Cat 4, is a type of twisted pair cable used in communication networks. It has been largely surpassed by more advanced cabling, but it was once mainly used for telephone and data communication, and can support signal transmission speeds up to 16 Mpbs over short distances.

What are the common uses of Category 4 cable?

Category 4 cable was primarily used for token ring networks and legacy telephone systems. However, due to its technical limitations, it has now been largely replaced by higher category cables such as Cat 5e, Cat 6, and Cat 6a, which offer faster transmission and better performance for modern telecommunications systems.

What is the maximum data transfer rate of Category 4 cable?

Category 4 cable has a maximum data transfer rate of 16 Mbps (megabits per second). This was considered a high-speed connection during the time when Cat 4 was widely used. However, most modern cabling options can support significantly faster data transfer rates.

What is the maximum length of Category 4 cable?

The maximum length of a Category 4 cable run should not exceed 90 meters (approximately 295 feet) for a single segment. This limitation is to ensure that the signal can be properly transmitted and received without excessive signal loss or degradation.

How is Category 4 cable different from other Ethernet cables?

Category 4 cable differs from other Ethernet cables due to its lower capacity to handle data transfer speeds, its limited range, and its twisted pair construction. With newer cabling options available, such as Cat 5e, Cat 6, and Cat 6a, the performance and capabilities of Category 4 cables are considered outdated for most modern network and communication applications.

Related Technology Terms

  • Twisted Pair Cabling
  • Unshielded Twisted Pair (UTP)
  • 10BASE-T Ethernet
  • 16 MHz Bandwidth
  • TIA/EIA-568-A Standard

Sources for More Information


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