Fiber optic Fire

A real cool picture of Fiber Optics

The Cladding, Buffer coating and Core of Fiber Optics

The cladding, core and Buffer coating in a fiber optic cable

Holding Fiber Optic cable

Here is a picture of a person holding a fiber optic picture in his hand.

Digital Fiber Optic Multichannel V/A/D Transport Systems

Fiber optics is now the dominant medium for terrestrial transmission of digital signals, and digital fiber optic systems are well established for transporting high quality video, audio, and data signals. Systems must make efficient use of optical fiber by transporting multiple channels of video and audio on a single fiber. A digital system working within a digital domain should be capable of expanding, inserting, routing, and switching signals within a network in such a way that video and audio performance is not affected. Of growing importance is the ability of these networks to accept a variety of signal formats and to interface with public television communication networks. Signal formats for transmission of video might include video encoding at various levels of digitizing accuracy, compressed video, advanced or high definition video, as well as digital high speed data. Understanding aspects of multiplexing, modulation schemes, and digital systems are important to implementing a multichannel transmission system.

All video/audio/data transport systems share a number of elements in common that form the basic system building blocks for any v/a/d system. These include: transmitters, receivers, signal regenerators, repeaters, coders, decoders, switches, modulators, amplifiers, A/D and D/A converters, splitters, combiners, signal fanouts, which allow signals to be added and dropped from a network or utilize smaller system components for the signal distribution, A/B switching for redundant circuit protection, network control data interfaces, and synchronizing clock interfaces.

Digital Video & HDTV

The FCC has set the year 2006 as the deadline for broadcasters to switch from standard definition television (SDTV) to digital television (DTV) and high-definition television (HDTV). Among the many advantages of this transition, transmission distance and repeater (signal regenerators) do not affect the quality of digitized video. A visit to any major broadcast industry trade show, such as those sponsored by the National Association of Broadcasters (NAB) or Society of Motion Pictures and Television Engineers (SMPTE), reveals that cameras, tape decks, mixing boards, matrix switches, effects boxes, etc. operate the digital format.

Fiber optics plays a big part in the move to the new television standards, providing the only viable means of signal transport by offering the bandwidth required for these television standards. Currently, analog video signals can be carried over relatively long lengths of coax cable. With a bandwidth of only 4.5 MHz, analog signals do not tax the limited bandwidth of coax cable, but even so, coax cable introduces a great deal of frequency dependent distortion requiring an equalization network. A digitized video signal's increased bandwidth usurps coax's ability to carry the new signal.

A standard NTSC video signal typically requires a serial bit rate of 143.2 Mb/s. By contrast, high-end HDTV standards require serial bit rates of 1,485 Mb/s. Coax cable can carry such high-speed digital data streams short distances, typically 300-600 meters for NTSC and 30-60 meters for HDTV. Fiber optics, on the other hand, can easily carry the full range of digital signals up to tens of thousands of meters.

Baseband Video Transmission

Baseband video consists of one video picture being sent point-to-point, such as the video output of a VCR to the video input of a monitor. Figure 1 illustrates simple point-to-point transmission. There exist two levels of service for baseband video: broadcast studio and consumer. These types describe, primarily, the quality of the signal. Broadcast studio quality requires a much higher signal fidelity, while consumer quality baseband requires is less demanding.

Broadband Video Transmission

Broadband Video Transmission

Broadband has become synonymous with “always on” Internet connections and digital high-definition television (HDTV). It describes the digital technologies that provide consumers with integrated access to voice, high-speed data services, video-on- demand (VOD), and interactive delivery services.

This transmission concept developed slowly, and carried many of promises along the way. Today, most of these promises are being realized. It is estimated that 21.2 million households will have broadband access by 2003. The FCC's Telecommunications Act of 1996 mandating that any communications business be allowed to compete in any market by 2006, affectively raising the performance bar, acts as a driving force to bring homes and industries into the broadband realm.

The numerous advantages of broadband, in addition to its speed, include enhanced picture quality, reliable transmission, and convenience. The convenience covers both television and computer use in the sense that the “always on” digital connection allows for video-on-demand and real-time interactions that before were not possible or severely limited in either media.
Broadband Applications

Broadband, a blanket term, describes an application that utilizes high speed, high bandwidth transmission. In the simplest description, broadband is merely a broader band through which information can pass; it is sometimes referred to as the "fat pipe." This means that multiple channels and can be transmitted digitally over a hybrid fiber coax or optical fiber at one time. The FCC requires that the quality of broadband, as an information service, carries a capacity of 200 kbps upstream, direction opposite the data flow or information from computer to the Internet, and downstream, direction of the data flow or information for the Internet to the computer. This carrying capacity accommodates the transmission of audio, video, and data services in an interactive format.

Internet connections like DSL and cable modems all use the broadband scheme. Table 1 illustrates the amount of time it takes to download a 30 second video clip from the Internet based on connection speed. The disparity among the different connection speeds makes it apparent that broadband allows for more advanced and demanding Internet applications.

Overview of Fiber Optic Communications Networks

All networks involve the same basic principle: information can be sent to, shared with, passed on, or bypassed within a number of computer stations (nodes) and a master computer (server). In addition to various topologies for networks, a number of standards and protocols have been developed, each with their own advantages, topologies, and medium requirements. This article discusses these standards and protocols, including: ATM, Ethernet, FDDI, Fibre Channel, ISDN, and SONET.
Asynchronous Transfer Mode (ATM)

Asynchronous transfer mode (ATM) is widely deployed as a network backbone technology. This technology integrates easily with other technologies, and offers sophisticated network management features that allow signal carriers to guarantee quality of service (QOS). ATM may also be referred to as cell relay because the network uses short, fixed length packets or cells for data transport. The information is divided into different cells, transmitted, and re-assembled at the receive end. Each cell contains 48 bytes of data payload as well as a 5-byte cell header. This fixed size ensures that time critical voice or video data will not be adversely affected by long data frames or packets.

ATM organizes different types of data into separate cells, allowing network users and the network itself to determine how bandwidth is allocated. This approach works especially well with networks handling burst data transmissions. Data streams are then multiplexed and transmitted between end user and network server and between network switches. These data streams can be transmitted to many different destinations, reducing the requirement for network interfaces and network facilities, and ultimately, overall cost of the network itself.

Connections for ATM networks include virtual path connections (VPCs), which contain multiple virtual circuit connections (VCCs). Virtual circuits are nothing more than end-to-end connections with defined endpoints and routes, but no defined bandwidth allocation. Bandwidth is allocated on demand as required by the network. VCCs carry a single stream of contiguous data cells from user to user. VCCs may be configured as static, permanent virtual connections (PVCs) or as dynamically controlled switched virtual circuits (SVCs). When VCCs are combined into VPCs, all cells in the VPC are routed the same way, allowing for faster recovery of the network in the event of a major failure.

While ATM still dominates WAN backbone configurations, an emerging technology, gigabit Ethernet, may soon replace ATM in some network scenarios, especially in LAN and desktop scenarios. A discussion of Ethernet follows.
Ethernet

Ethernet began as a laboratory experiment for Xerox Corporation in the 1970’s. Designers intended Ethernet to become a part of the “office of the future” which would include personal computer workstations. By 1980, formal Ethernet specifications had been devised by a multi-vendor consortium. Widely used in today’s LANs, Ethernet transmits at 10 Mb/s using twisted-pair coax cable and/or optical fiber. Fast Ethernet, transmits at 100 Mb/s, and the latest developing standard, gigabit Ethernet, transmits at 1,000 Mb/s or 1 Gb/s. Figure 1 illustrates the basic layout of an Ethernet network.

The formal Ethernet standard known as IEEE.802.3 uses a protocol called carrier sense multiple access with collision detection (CSMA/CD). This protocol describes the function of the three basic parts of an Ethernet system: the physical medium that carries the signal, the medium access control rules, and the Ethernet frame, which consists of a standardized set of bits used to carry the signal. Ethernet, fast Ethernet, and gigabit Ethernet all use the same platform and frame structure.

Ethernet users have three choices for physical medium. At 1 to 10 Mb/s, the network may transmit over thick coaxial cable, twisted-pair coax cable or optical fiber. Fast 100 Mb/s Ethernet will not transmit over thick coax, but can use twisted pair or optical fiber as well. Gigabit Ethernet, with greater data rate and longer transmission distance, uses optical fiber links for the long spans, but can also use twisted-pair for short connections.

CSMA/CD represents the second element, the access control rules. In this protocol, all stations must remain quiet for a time to verify no station in the network is transmitting before beginning a transmission. If another station begins to signal, the remaining stations will sense the presence of the signal carrier and remain quiet. All stations share this multiple access protocol. However, because not all stations will receive a transmission simultaneously, it is possible for a station to begin signaling at the same time another station does. This causes a collision of signals, which is detected by the station speaking out of turn, causing the station to become quiet until access is awarded, at which time the data frame is resent over the network.

The final element, the Ethernet frame, delivers data between workstations based on a 48-bit source and destination address field. The Ethernet frame also includes a data field, which varies in size depending on the transmission, and an error-checking field which verifies the integrity of the received data. As a frame is sent, each workstation Ethernet interface reads enough of the frame to learn the 48-bit address field and compares it with its own address. If the addresses match, the workstation reads the entire frame, but if the addresses do not match, the interface stops reading the frame.

Ethernet at all data rates has become a widely installed networks for LAN, MAN, and WAN applications. Its ability to interface with SONET and ATM networks will continue to support this popular network. In LANs, Ethernet links offer a scalable backbone, and a high speed campus data center backbone with inter-switch extensions. As a metro backbone in MANs, gigabit Ethernet will interface in DWDM systems, allowing long-haul, high speed broadband communications networks. Finally, Ethernet supports all types of data traffic including data, voice, and video over IP. Figure 2 illustrates a typical Ethernet deployment scenario.

Fibre Optic Picture

Web definations for Fiber Optics

Definitions of Fiber Optics on the Web:

Light transmission through optical fibers for communication or signaling.
logicalpackets.com/Network%20Learning/fiber_optic_glossary.htm

Thin filaments of glass through which light beams are transmitted over long distances and which can carry enormous amounts of data. Modulating l ight on thin strands of glass produces major benefits in high bandwidth, relatively low cost, low power consumption, small space needs, total insensitivity to electromagnetic interference, and great insensitivity to being bugged.
www.e-ratecentral.com/resources/help/glossary/f.asp

Thin glass filaments within a jacket or bundle that optically transmit images or signals in the form of light over distances, with extremely low high-bandwidth quality losses.
www.wgcu.org/watch/hdtv_glossaryofterms.html

Transmission technology in which modulated light-wave signals, generated by a laser or LED, are propagated along a glass or plastic medium, and then demodulated to electrical signals by a light sensitive receiver.
www.tecratools.com/pages/tecalert/lan_glossary.html

Hair-thin, flexible glass rods encased in cables that use light to transmit audio, video, and data signals.
www.acponline.org/computer/telemedicine/glossary.htm

The transmission of data in the form of pulses of light. Fiber optics uses cables containing glass or silica fibers no thicker than a human hair. There is very little signal loss, and information can be transmitted at high speed over long distances. Fiber optic cables do not have problems with external noise like wire cables do, and are better for transmissions requiring security.
www.startech.com/glossary/glossary.cfm

Technology based on thin filaments of glass or other transparent materials used as the medium for transmitting coded light pulses that represent data, image and sound. Fiber-optic technology offers extremely fast transmission speeds.
www.globalcrossing.com/xml/network/net_glossary.xml

Optical technology that deals with the transmission of light through fibers made up of transparent materials such as glass or plastic.
www.sarco.net/info/glossary.htm

cables made from bundles of glass or plastic fibers for high-bandwidth data transfer using beams of light carrying electromagnetic signals.
cyber.law.harvard.edu/readinessguide/glossary.html

An optical system in which an image is conveyed by a compact bundle of thin, flexible glass or plastic fibers. b
www.mise.org/mise/index.jsp

The technology of guiding and projecting light for use as a communications medium. Hair- thin glass fibers that allow light beams to be bent and reflected with low levels of loss and interference are known as "glass optical wave guides" or simply "optical fibers."
www.uri.edu/oherpt/gloss.html

The technology of transmitting and guiding optical radiation (light) along optical conductors
www.nuhorizons.com/Glossary/Optoelectronics.html

communications infrastructure that uses optical fibers for transmission. Optical fibers transmit large amounts of complex and varied information such as text, diagrams and graphics more quickly and efficiently than the traditional copper wires.
www.unesco.org/education/educprog/lwf/doc/portfolio/definitions.htm

The science of transmitting light by using very fine (thinner than a human hair), flexible glass fibers.
www.albanyinstitute.org/resources/archive/tiffany/tiffany.glossary.htm

Technology that involves sending laser light pulses via glass strands to transmit digital information. Strands, although about the thickness of a human hair, have nearly unlimited capacity. Bundled in protective sheathing about the diameter of a human thumb, fiber can carry more information than copper cable the diameter of a utility pole.
www.satelliteretailers.com/glossary.html

A strand of glass thinner than a human hair that is capable of carrying a light signal close to 70 miles without amplification. The light can be pulsed in a single wavelength to represent 45 Gigabits of information. Adding a wavelength doubles that capacity. In the year 2000, the wavelength technology is at 16 and growing.
www.popud.com/broadband_definitions.htm

An optical system that uses glass or transparent plastic fibers as light transmitting media. These cables have greater bandwidth than electrical transmission through wires.
www.vistek.ca/glossary/default.asp

Long, thin strands of glass that are used to transmit light impulses. These impulses are used to carry data that can be read by computers. Fiber optics are often used for super high-speed Internet access.
www.lastmileonline.com/broadbandterminology.htm

A medium using light for transmitting either an analog or digital signal. The signal loss is lower than that of coax cables and has a higher immunity to electromagnetic and static interference.
www.prosecuritywarehouse.com/techschool.html

Mode of transporting signals which uses laser beams through strands of glass.
www.satellite-commsys.com/glossary.php

A communications system which uses very thin strands of glass to conduct information coded in pulses of light.
www.odl.state.ok.us/servlibs/l-files/glossf.htm

A method of transmitting signals over light waves sent through extremely thin fibers spun from glass.
www.horizonmedia.com/glossary/f.htm

A medium that transmits voice, full-motion video, and data by sending light impulses through ultra-thin glass fibers. Fiber optics permits two-way, full motion video and two-way audio interaction between participating sites.
projects.edte.utwente.nl/ism/online96/project/kiosk/glossary.htm

(or optical fibers): Hair-thin strands of glass or plastic that use coded light signals, generated by lasers or light-emitting diodes, to transmit voice, video, or data signals. Offers wideband digital transmission. Integrated Services Digital Network (ISDN): The capability of providing an end-to-end digital network that would carry high speed data, voice, and video.
www.lib.niu.edu/ipo/im870721.html

A cable containing thin tubes permitting the exchange of electronic information for controlling substation activities from a remote point.
www.fs.fed.us/r3/carson/plans/ojo_caliente/html/glossary.html

the transmission of light signals via glass fibers
wordnet.princeton.edu/perl/webwn

An optical fiber is a transparent thin fiber, usually made of glass, for transmitting light. Fiber optics is the branch of science and engineering concerned with optical fibers.
en.wikipedia.org/wiki/Fiber_optics

Welcome to FiberOpticsPictures.blogspot.com

According to wikipedia, Fiber optics means

An optical fiber (or fibre) is a glass or plastic fiber designed to guide light along its length by confining as much light as possible in a propagating form. In fibers with large core diameter, the confinement is based on total internal reflection. In smaller diameter core fibers, (widely used for most communication links longer than 200m) the confinement relies on establishing a waveguide. Fiber optics is the overlap of applied science and engineering concerned with such optical fibers. Optical fibers are widely used in fiber-optic communication, which permits digital data transmission over longer distances and at higher data rates than other forms of wired and wireless communications. They are also used to form sensors, and in a variety of other applications.

The term optical fiber covers a range of different designs including graded-index optical fibers, step-index optical fibers, birefringent polarization-maintaining fibers and more recently photonic crystal fibers, with the design and the wavelength of the light propagating in the fiber dictating whether or not it will be multi-mode optical fiber or single-mode optical fiber. Because of the mechanical properties of the more common glass optical fibers, special methods of splicing fibers and of connecting them to other equipment are needed. Manufacture of optical fibers is based on partially melting a chemically doped preform and pulling the flowing material on a draw tower. Fibers are built into different kinds of cables depending on how they will be used.

The light-guiding principles behind optical fibers was first demonstrated in Victorian times, but modern optical fibers were only developed beginning in the 1950s. Optical fibers became practical for use in communications in the late 1970s, once the attenuation was reduced sufficiently, since then several technical advances have been made to improve the attenuation and dispersion properties of optical fibers, (allowing signals to travel further and carry more information), and lower the cost of fiber communications systems.