Cable is an essential component in any data communications network. The
media most commonly utilitzed ranges from coaxial and twinaxial cable, to fiber optic cabling.
to shielded-twisted pair(STP), to unshielded-twisted pair(UTP).Historically, coaxial cable was found in IBM mainframe environments to attach 3270 terminals and related peripherals to 3274 and 3174 cluster controllers. The first local area network, Arcnet utilized RG-62 coax. IBM midrange computers (Sys 36, 38 AS/400 etc.) initially used twinaxial cable to attach 5250 terminals and related peripherals. Two versions of coaxial Ethernet cable exist. The original Ethernet (10Base5) cable is .4 inches in diameter. Thin Ethernet (10Base2) which is .2 inches in diameter, was developed as a low cost alternative.
Fiber optics is a technology in which light is transmitted along the inside of a thin glass or plastic fiber. The fiber optic link converts an electrical signal to light for the purpose of connecting two electronic devices. Two type of fiber exist; mulitmode fiber and singlemode fiber. Historically, mulitmode fiber was used for data transmission while singlemode fiber is generally used voice requirements. Recently, Ethernet and Token Ring single mode transceivers have been developed. The most common applications for fiber include: FDDI (Fiber Distributed Data Interface) connections, Token Ring and Ethernet backbone connections.
Initially, the ST interface was the most common interface for 10BaseFL(10Mbps Ethernet over fiber) applications and Token Ring over fiber applications. Although the ST interface is still prevalent for 100BaseFX(100Mbps ethernet over fiber) applications, the SC has become very popular for 100BaseFX multimode fiber and singlemode fiber applications. THe MT-RJ is a new small-form factor connector that may become extremely popular for 100BaseFX applications. Some new 100BaseFX switches have an embedded MT-RJ connectors. Typically, adapter cables are needed to provide connectivity between network hardware and fiber optic patch panels. SC-ST adapters, SC-MT-RJ adapters and ST-MT-RJ adapters will continue to be extremely common for mulitimode and singlemode applications.
Shielded twisted pair (STP) is most common in token ring networks. STP token ring cables are typically terminated with a genderless (hermaphroditic) connector that shorts the two pairs when unplugged.
Unshielded twisted pair (UTP) has become the most popular media for local area networks. UTP are most often terminated with 8 conductor RJ45 modular connectors. UTP also has several different performance categories(Categories 1-5). The higher performance cables result from improved manufacturing techniques. Cat 3,4,5 are specified to support local area network requirements. Category 3 was designed to support data rates up to 10Mbps. Category 4 was designed to support 16Mpbs while Category 5 to support 100Mbps.
KMJ Communications provides UTP, STP and fiber optic patch cables, coxial cable and related cabling products.
Back to the Products Page
