Fiber Optics Illustrated Dictionary - Part 1 potx

Summers Protocols for Secure Electronic Commerce, Mostafa Hashem Sherif Protocols for Secure eCommerce, Second Edition, Mostafa Hashem Sherif After the Y2K Fireworks: Business and Techno

FIBER OPTICS

ILLUSTRATED DICTIONARY

Advanced and Emerging Communications

Technologies Series

Series Editor-in-Chief: Saba Zamir

The Telecommunications Illustrated Dictionary, Second Edition,

Julie K Petersen

Handbook of Emerging Communications Technologies: The Next Decade,

RafaelOsso

ADSL: Standards, Implementation, and Architecture, Charles K Summers

Protocols for Secure Electronic Commerce, Mostafa Hashem Sherif

Protocols for Secure eCommerce, Second Edition, Mostafa Hashem Sherif

After the Y2K Fireworks: Business and Technology Strategies,

Bhuvan Unhelkar

Web-Based Systems and Network Management, Kornel Terplan

Intranet Performance Management, Komel Terplan

Multi-Domain Communication Management Systems, Alex Galis

Fiber Optics Illustrated Dictionary, Julie K Petersen

IBER PTICS

ILLUSTRATED DICTIONARY

JULIE K PETERSENC

CRC PRESS

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About This Dictionary

The reader might assume that the process of writing or using a fiber optics dictionary is dry and uninteresting, but that really isn't the case Fiber optics is a vibrant field, not just in terms of its growth and increasing sophistication, but also in terms of the people, places, and details that make

up this challenging and rewarding industry

Fiber optics isn't as specialized as many people assume, either Fiber optics forms the heart of the telephone industry, the nervous system ofthe computer network industry, and the organs ofmany medical, dental, experimental, and satellite technologies That's part ofthe reason why this diction-ary is so big The Internet, the phone system, and wireless satellite systems are joined at the hip, with fiber optics landlines often supplemented by satellite links and vice versa

Fiber optics is attracting attention from many different sectors In Spring 2001, over 35,000 people from a wide variety of backgrounds attended a major international fiber optics conference

In spite of the inevitable peaks and slowdowns in the commercialization of any new technology, interest from professionals is growing and there are now thousands of training and certification courses for people who want to design, install, operate, and maintain fiber optic systems

The Quest for Communication by Light

The fiber optics industry is very recent; most of the significant developments have occurred in the last 60 years The application offiber to underlying telecommunications infrastructures became important in the 1980s and the use of fiber spread to consumer products and local area networks by the late 1990s

The history of fiber optics is based upon the efforts of many multitalented, tireless inventors, who traded social interactions for the thrill of discovery These pioneers were passionateintheir search for a way to communicate with light Alexander Graham Bell was more excited about his Photophone, a light-based telephone, than almost anything he ever invented, even though it was a commercial failure Bell recognized that he dido't have all the pieces of the puzzle to make it a viable technology and chose to move on, but that doesn't mean the Photophone was a bad idea; it just happened to be about 80 years ahead of its time

The earliest pioneers recognized certain potentially ground-breaking properties of optical ma-terials but weren't quite sure what made them work and, hence, were unable to fully harness their power For example, in the 1600s, Rasmus Bartholin thoroughly described the doubly refracting birefringent properties ofIceland spar, a type of transparent calcite, but wasn't able to work out the mathematics Later, both Wollaston and Nicol recognized Iceland spar could be assembled into new forms of prisms with special properties for controlling light, but it took many generations before scientists like Thomas Young began to unravel the mathematics that made this material so uniquely useful and applied that knowledge to describing the wavelike properties of light No sooner had scientists become comfortable with the idea of light behaving as waves when Max Planck set the stage, in 1900, for a particle theory of light and Einstein elaborated and applied the new ideas in quantum dynamics, leading to our current understanding of the photoelectric effect With the com-ing of the transistor and solid-state electronics, it was just a matter of time before smaller, less ex-pensive fiber-based components could be constructed

While optical science was evolving, the fabrication ofpure glass was advancing as well Many optical technologies in communications originated in much the same way as tongue depressors and penlights - doctors and dentists began using them to peer down people's throats

Scientists have long suspected that glass and light had capabilities far greater than anything yet imagined, but they weren't sure how to combine the two and still keep the signal within the lightguide

In terms of communications applications, this was a big road block

The idea of "bending" light isn't new; Colladon and Tyndall demonstrated it in the mid-1800s

by directing light inside an arc ofwater But the experiment remained an impractical curiosity until glass rods were shown to refract light in the same way Even so, the phenomenon ofrefraction needed

to be better understood before glass rods could be turned into effective fiber optic filaments

By the middle of the 20th century, a few innovative scientists began coating glass with other

refract off lower refractive index materials was fmally harnessed in the form of cladding, fiber op-tics became a practical reality From that point on, the quest for ideal proportions, purer glass, and more powerful, controllable light sources spurred the industry onto the next level of evolution In the 1950s, the development of lasers provided the essential energy source that finally launched the optical communications industry

With fiber optics now widely deployed, has it become just another ubiquitous technology, like telephone poles and automobiles? Perhaps in some ways this is true - cables for local area networks can be readily purchased on the Internet and optical couplers cost only a few dollars But that doesn't mean the industry has reached its limits or that the technology is no longer dynamically evolving Fiber-based networks are still in their infancy and the exploitation of the properties of light is still young and full ofpromise In addition, there are many areas ofinterest in which problems ofinstal-lation and deployment are tackled in innovative ways For example, the city of Houston has signed

an agreement to use a high-tech robot to navigate the city's sewers to connect hundreds ofpremises

to the fiber optic broadband networks to complete the "last mile" between the populace and the fiber backbone

Fiber optics is also becoming important in the signage, lighting, and medical industries Light-weight, inexpensive colored light-guides, side-emitting filaments, linelights, and pointlights all have exciting applications in architecture, interior design, industrial safety, marketing, finearts,and crafts Hobbyists are using fiber filaments to light scale models and train sets Inventive developers have created fiber optic "fabric" in which the fiber optic filaments are bent to deliberately release light at the joints where the weft crosses over the warp Doctors and dentists use fiber optics for imaging and surgery Wherever light is needed, there's a possibility a fiber optic filament can provide it

Purpose of the Dictionary

Itis the aim of this book to fill a gap in the literature on fiber optics There is only one signifi-cant fiber optics dictionary on the market and it was last published in 1998 Many advances have occurred since that time that deserve to be documented There is also a need for a text priced within the range of university students and technicians taking their certification training This dictionary can meet that need as well

Audience for the Dictionary

TheFiber Optics Illustrated Dictionaryis suitable for a wide variety ofbeginning profession-als in fiber optics, as well as students and instructors It will profession-also be of interest to professionprofession-als in other fields who want to get a beginning to intennediate introduction to optical technologies The book covers historical antecedents, network protocols for telephone and computer networks, satel-lite technologies, telephone terminology, basic physics concepts, and units ofmeasure important in optics It also explains many math and light-refracting concepts through a combination of words and pictures so that concepts that are hard to understand at first are explained in two ways This book does not attempt to duplicate the information in the FOLDOC online dictionary or the Federal Standards documents These dictionaries are readily available and searchable on the Internet and are well documented in Martin Weik's dictionary Instead, theFiber Optics Illustrated Dictionarytakes a current and comprehensive look at the fiber optics field and the various applica-tions of fiber optics, rounds out the picture with some introductory physics and fusion splicing in-formation, and presents it in a form that is illustrated, cross-referenced, and enhanced by historical biogfaphies and URL addresses for major not-for-profit and educational sites on the Web

I hope you enjoy using the book as much as I enjoyed preparing it (despite the long hours and endless search for accurate and often elusive information)

I am indebted to the hard work and enthusiasm ofthe professionals at CRC who helped bring it

to fruition, including Jerry Papke, who contributed the original concept, Chris Andreasen and the proofreading staff, who labored over many pages, and Jamie Sigal, Nora Konopka, and the folks in the production and marketing departments who all answered questions and moved the project along

Thanks also to Dawn Snider for her excellent interpretation of the cover

Julie K Petersen

About the Author

Julie K Petersen is a technology consultant, author, educator, and outdoor enthusiast, and readily admits

to being a technophile Her whole house is wired with computer and video links, both inside and out, and there's rarely a day when she isn't configuring some new piece of equipment to broadcast over a wireless transceiver Since TRS-80 computing days, she's been tweaking and fixing her own equipment and talks about configuring a wearable computer to interface directly with GPS data on the Internet

"The technology is already here; it's just a matter ofputting all the pieces together What you do

is take a head-worn display that projects an image on your retina with a laser beam that is eye-safe; such systems already exist Then you have a body-worn GPS sensor with an interface and wireless link to the Internet that goes through a geographical server The server matches your GPS coordinates with Web sites that offer information on maps, restaurants, nearby movie theaters, libraries, schools, etc You could have a profile online for your preferences, and the display would change as your location changes The process would be transparent, like a third eye, similar to the navigational images a fighter pilot sees projected over the landscape on the jet's transparent canopy, except even more natural I've named it theG-Eye™for geographic eye or GPS eye

The image projected on the user's retina by the G-Eyesystem would be tailor-made to the

·viewer's preferences It doesn't have to be a one-way communication either If the wearer were a professional on the job, like a newscaster or research scientist, he or she could be wearing sensors with fiber optic faceplates to sense body changes or changes in the surrounding environment, pressure, temperature, light levels, etc., that could be fed back to the computer network to act as a hands-free 'body interface' or a roving human sensing system The possibilities are endless Some people may see this as far-fetched, the idea of the human organism as a sort of sensory node on a distributed network, but young people readily understand and adapt to concepts such as this, especially if the new technology promotes or enhances social interactions, which this obviously could

TheG-Eyewould have been impractical a few years ago Compact diode lasers, sensors that could respond quickly, and high-bandwidth network links weren't yet sufficiently developed The limited capacity ofthe network infrastructure would have made such a two-way system impractical, but the new broadband fiber optic networks have astonishing speed and capacity, enough to individually outstrip the current collective traffic on the Internet It's feasible to imagine the entire human populace interconnected through a combination of wired and wireless optical links and satellites

Now equip the G-Eye with an optional digital video cam and microphone and you have an integrated network and digital phone/videoconferencing system that travels with you, instead of a half-dozen different, unconnected, bulky systems If there are interruptions in the network radio link, then you could carry a length of fiber optic cable that jacks into the nearest cafe or network vending machine for a clean wired link Fiber optic cables are lighter and more robust than most people realize If there's an emergency, the problem of clogged airwaves (familiar to traditional cell phone users) could be alleviated by people having these pocket cables integrated with their

G-Eyesystems as a backup to wireless connections There might even be an all-optical solution in certain circumstances Imagine free-air optical transceivers mounted on buildings (like small satellite receiving dishes) that people jack into with optical modems, somewhat like a two-way infrared remote control That way, if you're sitting in a park or at a sidewalk cafe, you could aim at a transceiver to maintain connectivity People have a tendency to thinkinterms of single solutions when often the best solution is a variety ofoptions Why put just forks in your cutlery drawer when there's room for knives and spoons as well?

Unfortunately, I haven't had time to build theG-Eyesystem The time demands of writing a comprehensive dictionary on the subject offiber optics, which changes even as it is documented, is considerable and my spare time is almost nonexistent, but I'm fascinated by the depth and breadth

of applications people are developing for optical waveguides, faceplates, and sensors and I'm sure there are many more surprises in store."

How to Use the

Fiber Optics Illustrated Dictionary

General Format There are two sections to this reference: (1) a main alphabetical body, with

nu-meral entries following Zand(2)several appendices with various charts, an extended section on ArM, a quick lookup acronym dictionary, and a timeline

of telecommunications inventions and technologies

bold-face,followed by its abbreviation or acronym, if applicable Pronunciation is included in cases where it may not be obvious Alternate names (e.g., William Thompsom, a.k.a Lord Kelvin) are cross-referenced The body of the entry is included next, with multiple definitions numbered if there are several mean-ings for a term Finally, where appropriate, there are cross-references, RFC list-ings, and URLs included at the end, in that order

Abbreviations In many cases, the term and its abbreviation are described together so the reader

doesn't have to look up abbreviated references to understand a particular entry; for example, cathode-ray tube will often be followed by (CRT) and Federal Com-munications Commission by (FCC) so the words and their commonly used ab-breviations become familiar to the reader

nonprofit, not-for-profit, charitable, and educational institutions and, in a few rare instances, for commercial enterprises with particular relevance for telecom-munications or with substantial educational content on their Web sites For the most part, commercial URLs are not included If the address isn't listed, it can often be guessed (http://www.companyname.com/) or otherwise easily located through Web search engines listed in Appendix D

RFCs Request for Comments (RFC) documents are an integral part of the Internet,

and extremely importantinterms of documenting the format and evolution of Internet protocols and technologies For this reason, RFC references are listed with many ofthe Internet-related references and can be found in numerous RFC repositories online There is also a partial list of significant or interesting RFC documents listed according to category in Appendix F

Diagrams and charts Illustrations are included as close to the related defmition as was possible in the

space provided Extensive listings of the various ITU-T Series Recommenda-tions are included in almost every chapter because they are the standards upon which most Internet technologies, telecommunications standards, and commer-cial products are built Charts are usually included on the same page as the re-lated definition or the one following

Bootstrap Protocol

-.l-"*r1r-tP1tT1rWccTileiennttlTs's;;;~ ns of stori ng and

pro-vid' ration information BOOTP evolved

in the ARPANET days to allow diskless client ma-chines, and other machines which Inight not kno\\' their own Internetaddresses~ to discover the IP ad-dress~the address ofa server host, and the name of

- - - a file tobeloaded into memoryandexecuted This

is accolnpl1shed in nvo phases: address determina-tion and bootfile selecdetermina-tion; and file transfer,

typi-cally \vith TFTP This has since evolved into Dy-namic Host Configuration Protocol (DHCP) See Address Resolution Protocol, Dynalnic Host Con-figuration Protocot Reverse Address Resolution

ro oc ~RFC 95l

http://www.urlgoeshere.org/

term or ph rase

definition

abbreviation or

acronym

pronunciation

cross-references

Web address (URL)

Request for Comments

reference number

Alphabetical Listings 1 Numerals 1043 Appendices 1049

A Fiber Optics Timeline 1050

B Asynchronous Transfer Mode (ATM) 1052

C lTU-T Series Recommendations 1055

D List ofWorld Wide Web Search Engines 1056

E List of Intemet Domain Name Extensions 1057

F Short List of Request for Comments (RFC) 1059

G National Associations 1062

H Dial Equivalents, Radio Alphabet, Morse Code,

Metric PrefixesNalues 1066

I ASCII Character and Control Codes 1067

a. 1 symb alpha, the first letter in the Greek

alpha-bet 2 symb angular acceleration 3 symb angle, in

geometry Along with~,often used in geometric

dia-grams to designate the angle of incidence or

refrac-tion or other angles associated with light paths

a 1 symb acceleration See Acceleration 2 symb.

anode See anode 3 abbrev area 4 symb atomic

mass 5 abbrev atto- See atto-.

A 1 symb acoustic velocity See acoustic velocity.

2 symb ampere See ampere 3 symb gain See gain.

A& Al leadsSeeAlAI.

A&BNumbers1 Designations for two ofthe

wire-less communication service categories available

through Inmarsat satellite relays Inmarsat A& B

ser-vices are commonly used for ship-to-shore

commu-nications The InmarsatA&B Numbersvary

depend-ing upon the ship and the selected satellite, but

in-clude voice, facsimile, and data lines See Inmarsat

for a chart of service categories 2 In mobile radio

systems in general, but especially cellular, the A

Num-beris a designation for the originating call point,

sig-naling towards the network, and the B Number is the

destination or answering point

A&B bitsignalingIn communications networks,

control or status information about the

communica-tions line itselfmay be interspersed with the data

con-tent that is being transmitted through that line This

is a form of in-band signaling A&B bit signaling is

a technique of inserting signal state information into

particular bits at intervals in the data transmission,

thus robbing a certain number of bits from the total

transmission For example, A bits are used in voice

communications implemented over Tt superframe (SF) networks to indicate outbound call signaling,

with B bits as mirrors to the A bits Through bit

rob-bing, the A and B signal bits are carried in each 6th and 12th frame, respectively, of each of the 24 T1 subchannels The types of supervisory information contained in these signal bits is relevant to switched voice or switched data services, including ring, busy, off-hook, and on-hook states.Inextended superframe (ESF), A, B, C, and D bits may be robbed from the 6th, 12th, 18th, and 24th frames

In some telephony systems, tone signaling is con-verted to A & B bit signaling for interoperability There is a trade-off when bits are robbed Since the available bits are not all used for data, the total throughput is less when measured over time How-ever, for less demanding voice communications, for example, the difference in speed and quality of the signal is not subjectively apparent to the listener Diagnostic Tt channel decoders typically show the

A and B bit signaling status, along with other alann, frame loss, or error conditions

NewerTl systems based upon bipolar eight-zero sub-stitution (B8ZS) don't use this bit-robbing technique SeeB8ZS

Abattery1 A low voltage battery historically used

to provide current to filaments or cathode heaters in electron tubes, now commonly used for small electronic appliances such as cameras, calculators, pen lights, etc See battery 2 A historic nonrechargeable

FCC-Designated Communications Frequency Blocks

Block Blk Size Frequency Paired Frequency Notes Date

A Block 30 MHz 1850-1865 MHz 1930-1945 MHz MTA Broadband PCS 1994-1995

B Block 30 MHz 1870-1885 MHz 1950-1965 MHz MTA Broadband PCS 1994-1995

C Block 30MHz 1895-1910 MHz 1975-1990 MHz BTA Broadband PCS 1995-1996

D Block 10 MHz 1865-1870 MHz 1945-1950 MHz BTA Broadband PCS 1996-1997 EBlock 10MHz 1885-1890 MHz 1965-1970MHz BTA Broadband PCS 1996-1997

F Block 10 MHz 1890-1895 MHz 1970-1975 MHz BTA Broadband PCS 1996-1997