CAT5 (sometimes called CAT 5 or Category 5 ) is an Ethernet network cable standard defined by the Electronic Industries Association and the Telecommunications Industry Association. CAT5 cable uses fifth generation twisted pair Ethernet technology and has become the most popular of all twisted pair cable types since its introduction in the 1990s.
CAT5 cable contains four pairs of copper wires and supports Fast Ethernet speeds up to 100 Mbps. As with all other types of twisted pair EIA/TIA cabling, the maximum recommended length of CAT5 cable is 100 meters (328 feet).
While CAT5 cable typically contains four pairs of copper wires, Fast Ethernet communications use only two pairs. EIA/TIA released an updated Category 5 cable specification in 2001, called CAT5e (or CAT5 Enhanced), designed to better support Gigabit Ethernet speeds up to 1000 Mbps by using all four pairs. CAT5e cables also retain backward compatibility with Fast Ethernet devices.
While Gigabit Ethernet is not technically supported, CAT5 cable is capable of supporting Gigabit speeds over shorter distances. The pairs in CAT5 cable are not as tightly twisted as pairs built to the CAT5e standard, so the risk of signal interference increases with distance.
Twisted pair cables such as CAT5 come in two main types: solid and stranded . Solid CAT5 cable supports longer distances and works best in fixed wiring configurations such as office buildings. Stranded CAT5 cable, on the other hand, is more flexible and better suited for short distances of removable cabling, such as dynamic patch cords.
Although newer cable technologies such as CAT6 and CAT7 were subsequently developed, Category 5 Ethernet cable remains the popular choice for most wired LANs due to the affordability and high performance of Ethernet equipment.
CAT5 Ethernet cables are easy to find in stores that sell electronics, including online stores. Some hobbyist builders and IT technicians build their own. At the very least, this skill would allow people to make cables to exactly the lengths they need. The process is not difficult to follow if you have a good understanding of color-coded wiring schemes and crimping tools.
Gigabit Ethernet already supports the speeds required for local networks, so it can be difficult to justify upgrading to CAT6 and newer standards, especially when most of the investment occurs in large enterprise environments where the rewiring effort can impose significant costs and Business interruption.
With the advent of wireless networking technology, some industry investment has shifted from developing wired Ethernet to wireless standards.