Network Cable Categories

Category 5 UTP cabling is the most widely used category of UTP cable. It enables transmission rates of up to 100 Mbps, and it is the highest category of UTP cabling.

UTP transmission rates:

Category 1 - up to 4 Mbps

Category 2 - up to 4 Mbps

Category 3 - up to 10 Mbps

Category 4 - up to 16 Mbps

Category 5 - up to 100 Mbps

Category 1 wiring consists of two pairs of twisted copper wire. It is rated for voice grade, not data communication. It is the oldest UTP wiring and is used for communication on the Public Switched Telephone Network (PSTN).

Category 2 wiring consists of four pairs of twisted copper wire and is suitable for data communications of up to 4 Mbps.

Category 3 wiring consists of four pairs of twisted copper wire with three twists per foot. It is suitable for 10 Mbps data communication. It has been the most widely used UTP standard since the mid 1980's, especially for Ethernet networks.

Category 4 wiring consists of four pairs of twisted copper wire and is rated for 16 Mbps. It was designed with 16 Mbps Token Ring networks in mind.

Category 5 wiring consists of four twisted pairs of copper wire terminated by RJ-45 connectors. Category 5 cabling can support frequencies of up to 100 MHz and speeds of up to 100 Mbps. It can be used for ATM, Token Ring, 1000Base-T, 100Base-T, and 10Base-T networking.

NOTE: Category 5e cable is the most commonly used cable for new UTP implementations. The "e" in Category 5e cable stands for "enhanced." This enhanced specification will support bandwidths of up to 350 MHz.

BNC connectors are used in 10Base2 Thinnet coaxial cable network implementations. The basic BNC connector is a male connector that looks similar to a connector you would use to plug into a television. It has a pin that connects to the primary conducting wire. The connector is locked in place by turning the outer ring.

Besides the BNC connector, there is a BNC T-connector and a BNC barrel connector. The BNC T-connector has three connection points forming the shape of a "T." Network cable goes into two of the connection points while the third point connects to a computer's network interface card. A BNC barrel connector has two connection points that are used to join two lengths of cable together.