A networking cable is a medium used to transfer data, information and controls from one device to another. Ethernet is the name given to a group of networked devices connected by cables to make a local area network or metropolitan area network. In the 1970’s, The Xerox Corporation developed an ISO- standardized Ethernet with copper as the preferred material for cables. A coaxial backbone cable was used, tapped into by smaller coaxial cables connecting each device. It had a speed of 10 Mbps and used a base band system(utilizes all its bandwidth)since then, several new types of cables have been developed, but the basic idea of connecting computers with plugged in cables remains.
Coaxial Cable
Emerging and ISO-approved in the 1980s, this cable is made with a central copper core wire wrapped in a dielectric insulator and a copper shield which insulates the core from external interference. This design make the entire cable quite stiff and unwieldy- not ideal for tight spaces or hiding in conduits. Coax wasn’t widely used.
Twisted Pair Cables
in the 1990’s emerged with an initial version called Cat 3 delivering 10 Mbps. It was quickly upgraded to 100 Mbps by the time Cat 5 came along, and finally up to a potential 10 Gbps in the latest iterations. Twisted Pair Cables are constructed by twisting two different insulated wires together and binding them in parallel inside a single cable housing. Twisting the cables at predetermined turns per foot helps prevent circuit noise from interfering with the intended signal
There are two types of twisted pair cables: Shielded twisted pair cable (STP) and unshielded pair cable (UTP). STP contains a shield on the inner conducting wire while UTP does not; it depends some other fancy physical properties of conductance to eliminate noise. The effectiveness of STP shielding depends on the material used; heavier materials make the cable heavier and stiffer resulting in difficulties during the installation process. The shielding can also bring about cross-talk and signal noise which needs to be compensated for. UTP varieties have been upgraded over the years and the newer ones are light, inexpensive, flexible and easier to install than STP
Here are some of the classifications of UTP cables you may have seen, in chronological order of development:
- Cat 1-only for telephone voice transmission- no data transmission
- Cat2-it has four twisted pair cables. Can transmit up to 4 Mbps
- Cat3-it has three twists per foot of the four twisted pair cables. Bandwidths up to 16 Mbps
- Cat4- transfers up to 20 Mbps.
- Cat5-transmits up to 100 Mbps.
Cat 7 and Cat 8
Cat 7 features shielding around each of four individual twisted pairs to avoid interference and has more conductors (4) to enable higher bandwidth. It’s also known as Screen Shielded Twisted Pair or Screened Foiled Twisted Pair. It potentially enables speeds up to 10 Gigabytes per second for an Ethernet. Cat 7 is currently in use as the best type of cable for distances up to 100 meters.
Cat 8 has been standardized by ISO/IEC 11801 and is currently available, although it’s still in the early stages of adoption. it will operate at a maximum frequency of 2.0 GHz, with 1.6 GHz being a normal operating frequency
Fiber Optic
This is a method of transmitting information by use of super-thin optical glass fibers. Data signals are converted to laser pulses which are then carried by the fiber to the receiver. The receiver uses a photoelectric cell which converts the laser pulses back to an electrical signal. The light signal bounces off the interior walls of the glass fiber and through internal reflection, the light beam is kept inside the fiber cable. This is done by including a layer of cladding in the inner wall of the fiber or “wire.” NetQ Media specializes in all forms of Fiber Optic installation.
Wireless Communication Media
This is a method of communication by use of electromagnetic waves with no wires are used. microwaves, infrared and radio frequencies are examples of electromagnetic waves. Although the signal is delivered to a broadcasting device with cables, once the signal is propagated, it can be boosted or received over wide distances with no connecting cables. Wireless solutions can often be cheaper to install, and can reach into remote areas with no access to traditional cabling technologies. They are also highly flexible; one does not need to be in a specific place, or possess the same device to communicate.
NetQ Media has long years of experience of both cutting edge and older technologies. For your next cabling project, call NetQ. We’re State of New Jersey contractors with experience in both public and private operations. Call us today with your questions: 800-303-4782
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