The vampire jack is a good name for one of the ways to insert data, the lifeblood of cyberspace, through cabling from one computer to another. The majority of computer networks use three classes of cabling: coaxial, twisted-pair (unshielded and shielded), and fiber-optic cable. Whether the computers and peripherals are networked by wireless or cable the flow of data will enter and leave the computers via the network adapter card. This article focuses on the uses of physical cabling connections and the variations in major cabling types.

Cabling surrounds us in our offices; much of it runs in the space between dropped ceilings and the structural ceilings so it can be extended down the walls and into the computers. Manufacturers make thousands of variations of cabling; only three major types connect the majority of networks: coaxial, twisted-pair (unshielded and shielded), and fiber-optic cable.

Coaxial cable consists of a copper core covered by a layer of foil insulation and braided metal shielding, and is referred to as dual shielded. In environments where there is unusually high interference there is coaxial cable with a second layer of foil insulation and another layer of braided metal shielding (quad shielding). The material that surrounds the solid copper core is meant to absorb stray electronic signals, or "noise" that would otherwise distort the data.

The outer protection from signal interference and electronic fields known as "crosstalk" from nearby wires is the braided shielding, or mesh. The transmitting copper core can't be allowed to come into contact with the metal mesh naturally or the metal-on-metal overflow of signals would cause a short circuit and destroy the data. To protect the copper wire, a layer of a thermoplastic polymer called Polyvinyl chloride (PVC) or Teflon is used. Over the core, insulation layer, and braided mesh of the cable there's a non-conducting outer shield of rubber or Teflon.

Coaxial cable is the workhorse of long-distance cabling because it doesn't suffer significant deterioration of the signal strength; this made the introduction of cable TV networks possible and practical for widespread use due to its ability to carry large data rates. When signal strength gets weaker and weaker over the distance of the cabling the technical term is attenuation. Any network cabling plan would take into consideration the quality of signal strength and amount of data to be transmitted.

A thick type of coaxial cable, or "thicknet" is used as the standard for heavy-duty connections where outside elements may damage wiring. There is also a thinnet coaxial cable about a quarter of an inch, that's more flexible and easy to work with in any kind of network cable installation. The thinnet center can be stranded wire or solid copper core; the signal attenuates past 185 meters so it is use for short connections.

Twisted-Pair cable is made up of two insulated copper wires twisted around each other; they also have unshielded and shielded types. An example of unshielded twisted-pair cabling is plain old telephone line. The twisting of the wires cancels out noise from other wires and nearby objects emitting electronic signals like motors or transformers. Like coaxial cable, the data isn't secured because it can be tapped and the data stolen.

In situations that involve more than just stealing the neighbor's cable, fiber-optic cable provides high-speed modulated pulses of light to send the data instead of electrical impulses. The data transmission is high-quality, extremely fast, and free of attenuation. Fiber-optic cable has a sending strand and a receiving strand. The core of each strand is made of extremely thin glass, surrounded a concentric glass layer called cladding. The complete cable is two stands covered by a protective jacket to give it sending and receiving capability.

Each type of network cabling has specifications for use and fire ordinance information to observe. Regular home and office standard cable connectors are familiar to most. Special care should be taken to have the correct configuration of the network adapter card; this can be a network adapter, a network interface card (NIC), a LAN adapter, or an Ethernet Controller. Ethernet defines a number of wiring and signaling standards for the physical layer of the standard networking model; Ethernet cable standards use all three cable types.

Speed of data transmission in megabits per second increases with technological breakthroughs to keep our computer networks humming along communicating efficiently while we as mere humans are left standing at home or in the office with our hands full of bunches of unfamiliar squid-like colored cables with strange-looking connectors, desperately trying to find which holes they go into.