Category 5 (Cat5) cabling became the standard for Ethernet networks in the 1990s because it provided a cost-effective and reliable solution for transmitting data at speeds up to 100Mbps. Prior to Cat5 cabling, Ethernet networks relied on coaxial and twisted-pair cables that had limited bandwidth and were prone to interference and crosstalk.

Cat5 cabling used twisted-pair copper wires that were more tightly wound than previous cables, which reduced interference and crosstalk. The tighter winding also allowed for higher data rates and longer cable runs without the need for signal boosters or repeaters. Additionally, Cat5 cabling was backward compatible with earlier Ethernet standards, making it easy to upgrade existing networks.

As Ethernet technology continued to evolve, the need for higher data rates and more reliable connections led to the development of Cat5e (enhanced) cabling. Cat5e cabling improved on the original Cat5 standard by reducing crosstalk and providing better performance at higher frequencies, allowing for data rates up to 1Gbps. Cat5e cabling quickly became the new standard for Ethernet networks and is still widely used today.

However, with the growing demand for even higher bandwidth and faster network speeds, the Cat5e standard was eventually surpassed by Cat6 cabling. Cat6 cabling offered even better performance at higher frequencies, allowing for data rates up to 10Gbps over shorter distances. This made it a popular choice for high-speed networks in data centers, office buildings, and other commercial applications.

As a result, Cat5 and Cat5e cabling began to be phased out in favor of Cat6 cabling. However, Cat5e cabling is still commonly used in many Ethernet networks due to its cost-effectiveness and compatibility with earlier Ethernet standards. Additionally, some newer standards, such as Power over Ethernet (PoE), require the use of Cat5e or better cabling to support higher power requirements.

In summary, the evolution of Ethernet cabling standards has been driven by the need for higher bandwidth, faster network speeds, and more reliable connections. While Cat5 and Cat5e cabling played a crucial role in the development of Ethernet networks, the invention of Cat6 cabling has made it possible to support even higher data rates and more demanding applications.