A wide variety of connectors can be used with fiber optic media,depending on the light emitting sources used to generate light pulses and the corresponding light-detecting sensors used to detect them,Figure 4-19 shows some connectors described in the following list: SC connector,ST connector,MT-RJ connector, LC connector.When the fiber optic patch cord ends of different interface, that can get a variety of fiber patch cable, such as LC-SC Patch Cord .
Fiber-optic cable trades electrical pulses for pulses light to represent bits.Because no electrical signals ever pass through the cable, fiber-optic media are as immune to electrical interference as any medium can get. Therefore, light pulses are unaffected by EMI and RFI.This characteristic also makes fiber-optic cables highly secure.They emit no external signals that might be detected, unlike electrical or broadcast media, there by eliminating the possibility of electronic eavesdropping.In particular, fiber optic cable is a good medium for high bandwidth, high speed,long-distance data transmission because of its lower attenuation characteristics and vastly higher bandwidth potential.Today, commercial implementations at 10,40, and 100 Gbps are in use.
Figure4-18 shows a typical fiber-optic cable.A slender cylinder of glass fiber called the core is surrounded by a concentric layer of glass called the cladding.The fibre is then jacketed in a thin transparent plastic material called the buffer.These three components make up to the mark what's labeled as the optical fiber in Figure 4-18.The fiber is optionally surrounded by an inner sheath made of colored plastic.A strengthening material, usually made of Kelar, comes next, followed by an outer sheath.Sometimes the core consists of plastic rather than glass fibers; plastic is more flexible and less sensitive to damage than glass, but attenuation is more of a problem than with glass.
Each fiber-optic strand carries data in only one direction,meaning fiber-optic network connections consist of two more strands,each in a separate inner sheath.However,these cables can be enclosed in a single sheath or can be two separate cables,each with its own sheath just as you have UTP patch cables,you also find fiber-optic patch cables,usually to connect from a fiber optic patch panel to a switch or router,Fiber optic patch cable used as back bone cabling often comes in bundles of 12 or more fiber strands,Even if you are using only two strands at first,it's good idea to run cable containing more fiber than you need ,in case a strand breaks during installation or you need additional strands for future growth.
Some testing has shown that glass fibers can carry several terabyte(1000 gigabytes) per second.There's really no end in sight for the bandwidth capacity of optical fiber.As network bandwidth needs s increase and the limits of copper wire are reached. Fiber optic cable will probably replace copper for all types of network connections,Table-4-2 summarizes fiber optic cablechareacteristics.And the singlemode fiber optic patch cables send one light signal at a time, and can be used for longer runs than multimode because they have more resistance to attenuation.Like the LC-LC Single Mode Patch Cord got a lot of applications in the everyday.
Medium interface connector-A medium interface connector is utilized to fiber distributed data interface like SC connectors MIC connectors are one-piece constructions.
Straight tip-Straight tip(ST) connectors join fibers of cross-connects or to optical devices.They are used most often in ethernet networks with fiber -optic cable as backbone cabling.ST connector locks onto the jack when twisted.
Straight connection-straiht connection(SC) connectors push on,which makes them easy to install and requires space for an attachment.They make a strong connection and can be used when splicing fiber-optic cables, a SC connector is a one -piece component, with two receptacles, fiber optic cables, a notch in its jacket ensures the correct orientation when inserted.
Locking connection-locking connection(LC) connectors push on and pull off with an RJ-45 style latching mechanism.The LC LC Fiber Patch Cord is adopted this connector on both ends here.They are about half the size of SC connectors, which make them good for high-desity applications, in which many fibers are concentrated in one location.
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