Coaxial cable consists of a center conductor, either stranded or solid, which is surrounded by a layer of insulating material called the dielectric. The dielectric is surrounded by a shield made of foil, braided wire strands, or both. Outside of the shield is a protective insulating sheath that forms the cable jacket.
All of the elements of the coaxial cable encircle the center conductor, as the growth rings in a tree surround the core. Because they all share the same axis, this construction is called coaxial, or coax for short. Coax is the most widely used media for transporting high radio frequency signals over wire, especially cable television signals. The cables leading to most external antennas are coax. The video cables that connect a VCR to a TV are coax. Miles of coax are found in most video production facilities.
In the past, coaxial cable offered significant advantages for LANs. Its frequency response allowed it to carry signals with less degradation over longer distances than the twisted pair media available at the time. Improved manufacturing techniques and better electronics have long made twisted pair or optical fibers the preferred choice for network cabling.
Originally, Ethernet LANs used a thick coaxial cable that was 1.27 cm (0.5 inches) in diameter. The industry began to refer to this cable as Thicknet . The large coax used for 10Base5 networks was particularly difficult to work with and required great care to prevent bends and kinks. When Ethernet was standardized, Thicknet became IEEE 802.3 10Base5.
Later, the 802.3 committee standardized 10Base2, a version that used a much thinner coaxial cable, with an outside diameter of only 0.635 cm (0.25 in.). 10Base2 is sometimes referred to as Thinnet. Because of its low cost and ease of installation, it is also sometimes referred to as cheapernet.
All of the elements of the coaxial cable encircle the center conductor, as the growth rings in a tree surround the core. Because they all share the same axis, this construction is called coaxial, or coax for short. Coax is the most widely used media for transporting high radio frequency signals over wire, especially cable television signals. The cables leading to most external antennas are coax. The video cables that connect a VCR to a TV are coax. Miles of coax are found in most video production facilities.
In the past, coaxial cable offered significant advantages for LANs. Its frequency response allowed it to carry signals with less degradation over longer distances than the twisted pair media available at the time. Improved manufacturing techniques and better electronics have long made twisted pair or optical fibers the preferred choice for network cabling.
Originally, Ethernet LANs used a thick coaxial cable that was 1.27 cm (0.5 inches) in diameter. The industry began to refer to this cable as Thicknet . The large coax used for 10Base5 networks was particularly difficult to work with and required great care to prevent bends and kinks. When Ethernet was standardized, Thicknet became IEEE 802.3 10Base5.
Later, the 802.3 committee standardized 10Base2, a version that used a much thinner coaxial cable, with an outside diameter of only 0.635 cm (0.25 in.). 10Base2 is sometimes referred to as Thinnet. Because of its low cost and ease of installation, it is also sometimes referred to as cheapernet.